Recursive CTE didn't track memory accurately

[guo-shaoge]

Bug Report

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1. Minimal reproduce step (Required)

tidb/pkg/util/cteutil/storage.go

Lines 156 to 169 in 6695d5e

	// Reopen impls Storage Reopen interface.
	func (s *StorageRC) Reopen() (err error) {
	if err = s.rc.Close(); err != nil {
	return err
	}
	s.iter = 0
	s.done = false
	s.err = nil
	// Create a new RowContainer.
	// Because some meta infos in old RowContainer are not resetted.
	// Such as memTracker/actionSpill etc. So we just use a new one.
	s.rc = chunk.NewRowContainer(s.tp, s.chkSize)
	return nil
	}

L167 create a new row container after each CTE iteration. But it didn't attach memtracker to session tracker, so the memory control will not work correctly.

Specifically, the memory control for resTbl of CTE is as expected, but after one iteration of the CTE computation, the memory usage of iterInTbl and iterOutTbl cannot be accurately tracked (and they also cannot be spilled to disk) because of above bug.

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

3. What did you see instead (Required)

4. What is your TiDB version? (Required)