*: fix cte nil pointer error when got multiple apply (#44782)

[ti-chi-bot]

This is an automated cherry-pick of #44782

What problem does this PR solve?

Issue Number: close #44774

Problem Summary:
The following plan:

Apply-1
    outerSide
    Apply-2
        CTE-1(access CTEProducer-1)
        CTE-2(access CTEProducer-1)

CTEProducer-1 has corCol, which is one of columns of Apply-1's outerSide output)

If CTE-1 and CTE-2 both access the same CTE Producer(a.k.a. same CTE defition), we use CTEExec.IsInApply to control whether reopen CTEStorage.

But CTE.IsInApply is not enough here, because CTE-1 and CTE-2 only need to reopen when Apply-1 runs, no need to reopen when Apply-2 runs.

What is changed and how it works?

Before: Always reopen CTEStorage/CTEProducer when CTE.IsInApply is true.

After: Only reopen CTEStorage/CTEProducer when the data of corCol changes.

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No code

Side effects

• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Breaking backward compatibility

Documentation

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Changes MySQL compatibility

Release note

Please refer to Release Notes Language Style Guide to write a quality release note.

None

[ti-chi-bot]

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[guo-shaoge]

Block by #44777 and #43645