[fix](fe-ut) make SetVariableTest::testExecMemLimit more reasonable

[mrhhsg]

What problem does this PR solve?

And also fix the WorkloadGroupTest::testCreateNormal

After merged the spill and reserve code(#47462), the properties of WorkloadGroup was changed.

Problem Summary:

Release note

None

Check List (For Author)

• Test

  • Regression test
  • Unit Test
  • Manual test (add detailed scripts or steps below)
  • No need to test or manual test. Explain why:
    • This is a refactor/code format and no logic has been changed.
    • Previous test can cover this change.
    • No code files have been changed.
    • Other reason

• Behavior changed:

  • No.
  • Yes.

• Does this need documentation?

  • No.
  • Yes.

Check List (For Reviewer who merge this PR)

• Confirm the release note
• Confirm test cases
• Confirm document
• Add branch pick label

[Thearas]

Thank you for your contribution to Apache Doris.
Don't know what should be done next? See How to process your PR.

Please clearly describe your PR:

1. What problem was fixed (it's best to include specific error reporting information). How it was fixed.
2. Which behaviors were modified. What was the previous behavior, what is it now, why was it modified, and what possible impacts might there be.
3. What features were added. Why was this function added?
4. Which code was refactored and why was this part of the code refactored?
5. Which functions were optimized and what is the difference before and after the optimization?

[mrhhsg]

run buildall

[mrhhsg]

run buildall

[doris-robot]

TPC-H: Total hot run time: 31677 ms

machine: 'aliyun_ecs.c7a.8xlarge_32C64G'
scripts: https://github.com/apache/doris/tree/master/tools/tpch-tools
Tpch sf100 test result on commit 09f1487e18f6b5635cb75f806e31aaf7ada5ec29, data reload: false

------ Round 1 ----------------------------------
q1	17606	5253	5085	5085
q2	2061	304	173	173
q3	10401	1293	689	689
q4	10206	1031	530	530
q5	7498	2411	2400	2400
q6	187	171	137	137
q7	927	760	589	589
q8	9321	1209	1111	1111
q9	4835	4942	4746	4746
q10	6809	2312	1906	1906
q11	478	283	273	273
q12	357	351	218	218
q13	17772	3672	3071	3071
q14	226	230	203	203
q15	497	469	460	460
q16	643	611	571	571
q17	562	859	340	340
q18	6619	6304	6241	6241
q19	1222	947	520	520
q20	311	321	189	189
q21	2652	2234	1927	1927
q22	369	334	298	298
Total cold run time: 101559 ms
Total hot run time: 31677 ms

----- Round 2, with runtime_filter_mode=off -----
q1	5112	5128	5124	5124
q2	236	329	225	225
q3	2183	2669	2326	2326
q4	1433	1851	1377	1377
q5	4245	4099	4181	4099
q6	206	160	121	121
q7	1869	1800	1648	1648
q8	2573	2522	2556	2522
q9	7277	7179	7130	7130
q10	2988	3213	2762	2762
q11	579	501	494	494
q12	674	764	613	613
q13	3516	3896	3238	3238
q14	285	291	260	260
q15	513	469	473	469
q16	618	675	620	620
q17	1118	1585	1317	1317
q18	7647	7351	7247	7247
q19	794	779	834	779
q20	1950	2002	1854	1854
q21	5365	4986	4799	4799
q22	649	602	534	534
Total cold run time: 51830 ms
Total hot run time: 49558 ms

[doris-robot]

TPC-DS: Total hot run time: 184440 ms

machine: 'aliyun_ecs.c7a.8xlarge_32C64G'
scripts: https://github.com/apache/doris/tree/master/tools/tpcds-tools
TPC-DS sf100 test result on commit 09f1487e18f6b5635cb75f806e31aaf7ada5ec29, data reload: false

query1	972	404	382	382
query2	6644	1881	1853	1853
query3	6791	211	204	204
query4	26526	23648	23627	23627
query5	5291	656	484	484
query6	303	202	187	187
query7	4607	494	293	293
query8	313	235	227	227
query9	8692	2516	2507	2507
query10	501	320	264	264
query11	15515	15160	15013	15013
query12	158	108	107	107
query13	1653	514	379	379
query14	10269	6506	6158	6158
query15	204	196	191	191
query16	7548	656	409	409
query17	1154	724	554	554
query18	1963	403	300	300
query19	194	187	160	160
query20	122	116	115	115
query21	209	127	105	105
query22	4086	4537	4585	4537
query23	34425	33250	32826	32826
query24	7704	2354	2347	2347
query25	524	455	380	380
query26	1235	269	153	153
query27	2107	494	329	329
query28	3886	2392	2371	2371
query29	689	531	411	411
query30	233	193	155	155
query31	942	863	786	786
query32	67	67	67	67
query33	573	363	310	310
query34	778	844	493	493
query35	793	823	737	737
query36	948	986	886	886
query37	118	99	76	76
query38	4126	4333	4243	4243
query39	1456	1377	1388	1377
query40	202	114	98	98
query41	54	51	50	50
query42	119	107	101	101
query43	497	498	480	480
query44	1285	786	799	786
query45	175	172	163	163
query46	857	1030	633	633
query47	1753	1778	1699	1699
query48	370	404	295	295
query49	769	490	449	449
query50	677	734	411	411
query51	4158	4219	4122	4122
query52	114	106	95	95
query53	220	258	184	184
query54	485	476	416	416
query55	84	76	81	76
query56	265	275	239	239
query57	1115	1131	1061	1061
query58	250	243	268	243
query59	2494	2573	2543	2543
query60	292	278	276	276
query61	145	140	143	140
query62	795	715	693	693
query63	229	193	189	189
query64	4398	974	661	661
query65	3173	3135	3125	3125
query66	1028	406	348	348
query67	15564	15300	15277	15277
query68	9606	872	513	513
query69	490	298	259	259
query70	1188	1100	1078	1078
query71	472	296	270	270
query72	5242	3527	3826	3527
query73	782	730	350	350
query74	9238	8865	9092	8865
query75	4336	3205	2722	2722
query76	3796	1166	730	730
query77	998	368	275	275
query78	10135	10033	9294	9294
query79	2432	890	590	590
query80	602	528	455	455
query81	518	286	240	240
query82	706	126	96	96
query83	170	173	162	162
query84	245	97	77	77
query85	791	342	312	312
query86	374	294	282	282
query87	4435	4446	4417	4417
query88	3645	2228	2207	2207
query89	394	316	290	290
query90	1954	196	195	195
query91	141	141	106	106
query92	81	64	57	57
query93	1691	1052	587	587
query94	655	403	331	331
query95	351	271	267	267
query96	482	558	270	270
query97	3348	3403	3275	3275
query98	235	207	205	205
query99	1534	1405	1280	1280
Total cold run time: 276953 ms
Total hot run time: 184440 ms

[doris-robot]

ClickBench: Total hot run time: 30.77 s

machine: 'aliyun_ecs.c7a.8xlarge_32C64G'
scripts: https://github.com/apache/doris/tree/master/tools/clickbench-tools
ClickBench test result on commit 09f1487e18f6b5635cb75f806e31aaf7ada5ec29, data reload: false

query1	0.04	0.03	0.03
query2	0.07	0.04	0.03
query3	0.23	0.07	0.07
query4	1.61	0.10	0.10
query5	0.56	0.54	0.56
query6	1.19	0.72	0.72
query7	0.02	0.01	0.02
query8	0.04	0.04	0.03
query9	0.57	0.55	0.52
query10	0.57	0.58	0.57
query11	0.15	0.10	0.10
query12	0.14	0.11	0.10
query13	0.61	0.59	0.59
query14	2.72	2.68	2.82
query15	0.92	0.85	0.84
query16	0.38	0.39	0.38
query17	1.02	1.03	1.03
query18	0.22	0.20	0.19
query19	1.88	1.78	1.99
query20	0.01	0.01	0.01
query21	15.36	0.92	0.55
query22	0.76	1.18	0.73
query23	14.88	1.38	0.63
query24	7.37	1.27	0.84
query25	0.53	0.11	0.19
query26	0.57	0.16	0.14
query27	0.05	0.05	0.05
query28	9.60	0.87	0.43
query29	12.55	4.04	3.28
query30	0.25	0.08	0.07
query31	2.80	0.59	0.38
query32	3.22	0.53	0.45
query33	3.01	3.02	2.98
query34	15.80	5.10	4.51
query35	4.49	4.50	4.54
query36	0.67	0.50	0.49
query37	0.09	0.06	0.06
query38	0.05	0.04	0.03
query39	0.03	0.02	0.02
query40	0.17	0.13	0.13
query41	0.08	0.03	0.02
query42	0.04	0.03	0.02
query43	0.03	0.04	0.03
Total cold run time: 105.35 s
Total hot run time: 30.77 s

[github-actions]

PR approved by at least one committer and no changes requested.

[github-actions]

PR approved by anyone and no changes requested.

[hello-stephen]

skip buildall