flaky case TestPhysicalTableScanExtractCorrelatedCols

[D3Hunter]

Bug Report

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1. Minimal reproduce step (Required)

https://do.pingcap.net/jenkins/blue/rest/organizations/jenkins/pipelines/pingcap/pipelines/tidb/pipelines/ghpr_unit_test/runs/4227/nodes/63/steps/69/log/?start=0

    physical_plan_test.go:495: 
        	Error Trace:	pkg/planner/core/physical_plan_test.go:495
        	Error:      	Not equal: 
        	            	expected: 1
        	            	actual  : 0
        	Test:       	TestPhysicalTableScanExtractCorrelatedCols

2. What did you expect to see? (Required)

3. What did you see instead (Required)

4. What is your TiDB version? (Required)

master