branch-3.0: [fix](webui) add connection context to avoid NPE #49213

[github-actions]

Cherry-picked from #49213

[hello-stephen]

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?

[hello-stephen]

run buildall

[doris-robot]

TPC-H: Total hot run time: 39982 ms

machine: 'aliyun_ecs.c7a.8xlarge_32C64G'
scripts: https://github.com/apache/doris/tree/master/tools/tpch-tools
Tpch sf100 test result on commit ebf4222428ef9669c0ae722c3809e21108e2f0fc, data reload: false

------ Round 1 ----------------------------------
q1	17625	6729	6639	6639
q2	2057	178	168	168
q3	10590	1070	1238	1070
q4	10547	775	668	668
q5	7747	2813	2729	2729
q6	217	132	132	132
q7	975	622	604	604
q8	9355	1935	2000	1935
q9	6532	6385	6343	6343
q10	7020	2261	2307	2261
q11	461	263	259	259
q12	398	209	211	209
q13	17774	2999	3003	2999
q14	240	204	204	204
q15	513	471	463	463
q16	672	581	576	576
q17	960	592	584	584
q18	7203	6693	6666	6666
q19	1463	1036	1070	1036
q20	474	215	205	205
q21	4098	3240	3319	3240
q22	1113	999	992	992
Total cold run time: 108034 ms
Total hot run time: 39982 ms

----- Round 2, with runtime_filter_mode=off -----
q1	6545	6503	6519	6503
q2	325	236	226	226
q3	2923	2787	2861	2787
q4	2035	1802	1821	1802
q5	5737	5719	5731	5719
q6	216	134	130	130
q7	2179	1845	1827	1827
q8	3383	3538	3505	3505
q9	8849	8961	8961	8961
q10	3618	3582	3556	3556
q11	607	489	506	489
q12	807	629	597	597
q13	8351	3212	3170	3170
q14	308	268	270	268
q15	512	478	470	470
q16	691	644	629	629
q17	1828	1601	1585	1585
q18	8213	7790	7584	7584
q19	1647	1425	1512	1425
q20	2096	1881	1861	1861
q21	5437	5262	5295	5262
q22	1154	1030	1013	1013
Total cold run time: 67461 ms
Total hot run time: 59369 ms

[doris-robot]

TPC-DS: Total hot run time: 196352 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 ebf4222428ef9669c0ae722c3809e21108e2f0fc, data reload: false

query1	1272	912	904	904
query2	6242	2143	2119	2119
query3	10998	4591	4441	4441
query4	32576	23291	23569	23291
query5	3620	474	447	447
query6	272	186	188	186
query7	3984	328	323	323
query8	290	225	224	224
query9	9568	2613	2597	2597
query10	445	254	264	254
query11	17868	15101	15341	15101
query12	166	101	106	101
query13	1546	432	406	406
query14	8713	6410	6670	6410
query15	226	177	176	176
query16	8037	445	520	445
query17	1604	581	559	559
query18	2155	316	325	316
query19	219	164	172	164
query20	126	119	118	118
query21	205	112	112	112
query22	4674	4597	4410	4410
query23	34998	34182	33966	33966
query24	12217	2868	2942	2868
query25	702	437	407	407
query26	1858	174	172	172
query27	3048	387	355	355
query28	7730	2440	2454	2440
query29	1077	469	454	454
query30	284	162	168	162
query31	1030	836	861	836
query32	97	60	62	60
query33	782	319	314	314
query34	977	507	512	507
query35	868	749	772	749
query36	1148	971	999	971
query37	270	68	66	66
query38	4115	3969	4065	3969
query39	1556	1454	1478	1454
query40	259	106	103	103
query41	51	52	55	52
query42	117	106	104	104
query43	545	511	498	498
query44	1299	842	826	826
query45	193	175	169	169
query46	1201	747	760	747
query47	2072	1916	1989	1916
query48	493	397	392	392
query49	1033	404	382	382
query50	829	430	421	421
query51	7492	7278	7371	7278
query52	103	91	98	91
query53	261	185	187	185
query54	1164	469	464	464
query55	80	77	78	77
query56	277	276	260	260
query57	1295	1176	1159	1159
query58	226	209	220	209
query59	3375	3277	3114	3114
query60	303	279	266	266
query61	111	144	112	112
query62	862	688	690	688
query63	220	200	194	194
query64	4970	689	654	654
query65	3262	3157	3181	3157
query66	1317	305	293	293
query67	15816	15513	15522	15513
query68	4881	584	571	571
query69	436	291	258	258
query70	1212	1126	1115	1115
query71	353	257	245	245
query72	6172	3851	4059	3851
query73	748	348	360	348
query74	9820	8983	8846	8846
query75	3336	2614	2641	2614
query76	2627	1111	1019	1019
query77	363	277	281	277
query78	10505	9554	9617	9554
query79	1481	592	585	585
query80	866	431	433	431
query81	560	244	234	234
query82	538	91	85	85
query83	253	151	144	144
query84	234	80	81	80
query85	1405	296	289	289
query86	420	303	300	300
query87	4538	4249	4259	4249
query88	4250	2408	2379	2379
query89	407	290	290	290
query90	1959	183	186	183
query91	185	146	160	146
query92	59	51	49	49
query93	2450	556	559	556
query94	799	296	305	296
query95	362	258	257	257
query96	610	280	281	280
query97	3358	3185	3142	3142
query98	219	203	204	203
query99	1494	1298	1299	1298
Total cold run time: 303689 ms
Total hot run time: 196352 ms

[doris-robot]

ClickBench: Total hot run time: 32.38 s

machine: 'aliyun_ecs.c7a.8xlarge_32C64G'
scripts: https://github.com/apache/doris/tree/master/tools/clickbench-tools
ClickBench test result on commit ebf4222428ef9669c0ae722c3809e21108e2f0fc, data reload: false

query1	0.03	0.04	0.03
query2	0.07	0.04	0.03
query3	0.24	0.07	0.06
query4	1.62	0.10	0.10
query5	0.53	0.50	0.50
query6	1.13	0.72	0.73
query7	0.02	0.02	0.02
query8	0.05	0.03	0.03
query9	0.56	0.50	0.49
query10	0.53	0.55	0.55
query11	0.14	0.10	0.10
query12	0.14	0.11	0.11
query13	0.60	0.60	0.59
query14	2.73	2.75	2.76
query15	0.93	0.84	0.83
query16	0.38	0.36	0.39
query17	1.00	1.05	1.00
query18	0.25	0.22	0.23
query19	1.82	1.88	2.01
query20	0.01	0.02	0.02
query21	15.37	0.58	0.56
query22	2.42	2.99	1.54
query23	16.97	0.99	0.83
query24	3.26	1.50	1.95
query25	0.30	0.07	0.21
query26	0.58	0.16	0.13
query27	0.04	0.04	0.05
query28	8.96	0.57	0.48
query29	12.59	3.21	3.21
query30	0.26	0.05	0.05
query31	2.87	0.38	0.38
query32	3.26	0.46	0.45
query33	2.94	3.03	3.06
query34	17.06	4.48	4.59
query35	4.48	4.47	4.60
query36	0.69	0.48	0.47
query37	0.09	0.06	0.06
query38	0.04	0.03	0.04
query39	0.04	0.02	0.02
query40	0.16	0.13	0.12
query41	0.07	0.03	0.02
query42	0.04	0.02	0.02
query43	0.04	0.03	0.03
Total cold run time: 105.31 s
Total hot run time: 32.38 s

[dataroaring]

LGTM