flaky test TestGlobalStatsAndSQLBindingWithConcurrency

[hawkingrei]

Bug Report

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         	Error Trace:	pkg/testkit/testkit.go:335
        	            				pkg/statistics/handle/globalstats/global_stats_internal_test.go:451
        	            				pkg/statistics/handle/globalstats/global_stats_test.go:976
        	Error:      	Should be true
        	Test:       	TestGlobalStatsAndSQLBindingWithConcurrency
        	Messages:   	select * from thash where a<100 doesn't have plan TableFullScan, full plan [[IndexLookUp_10 9.07 root partition:all ] [├─IndexRangeScan_8(Build) 9.07 cop[tikv] table:thash, index:a(a) range:[-inf,100), keep order:false] [└─TableRowIDScan_9(Probe) 9.07 cop[tikv] table:thash keep order:false]] 

https://tiprow.hawkingrei.com/view/gs/pingcapprow/pr-logs/pull/pingcap_tidb/60342/fast_test_tiprow/1906631632421392384#1:build-log.txt%3A3586

4. What is your TiDB version? (Required)