IT Unstable case TestGetIndexMVCC

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Bug Report

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in ci https://ci.pingcap.net/blue/organizations/jenkins/tidb_ghpr_coverage/detail/tidb_ghpr_coverage/1412/pipeline

2021-11-30T11:48:42.472Z] --- FAIL: TestGetIndexMVCC (1.37s)
[2021-11-30T11:48:42.472Z]     dbtestkit.go:72: 
[2021-11-30T11:48:42.472Z]         	Error Trace:	dbtestkit.go:72
[2021-11-30T11:48:42.472Z]         	            				http_handler_test.go:505
[2021-11-30T11:48:42.472Z]         	            				http_handler_test.go:748
[2021-11-30T11:48:42.472Z]         	Error:      	Received unexpected error:
[2021-11-30T11:48:42.472Z]         	            	commands out of sync. Did you run multiple statements at once?
[2021-11-30T11:48:42.472Z]         	Test:       	TestGetIndexMVCC
[2021-11-30T11:48:42.472Z]         	Messages:   	sql:create database tidb;, args:[]
[2021-11-30T11:48:42.472Z]     http_handler_test.go:501: 
[2021-11-30T11:48:42.472Z]         	Error Trace:	http_handler_test.go:501
[2021-11-30T11:48:42.472Z]         	            				panic.go:613
[2021-11-30T11:48:42.472Z]         	            				testing.go:741
[2021-11-30T11:48:42.472Z]         	            				dbtestkit.go:72
[2021-11-30T11:48:42.472Z]         	            				http_handler_test.go:505
[2021-11-30T11:48:42.472Z]         	            				http_handler_test.go:748
[2021-11-30T11:48:42.472Z]         	Error:      	Received unexpected error:
[2021-11-30T11:48:42.472Z]         	            	bad connection
[2021-11-30T11:48:42.472Z]         	Test:       	TestGetIndexMVCC

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[mjonss]

Related to #30249 ?

[djshow832]

Related to #30249 ?

I think so. There are at least 5 relevant issues.

[hawkingrei]

Closed #30306. We can re-open it if the error happens again.

[github-actions]

Please check whether the issue should be labeled with 'affects-x.y' or 'fixes-x.y.z', and then remove 'needs-more-info' label.