statistics: delete old partition's stats meta after removing partitioning

[Rustin170506]

What problem does this PR solve?

Issue Number: close #49547

Problem Summary:

What changed and how does it work?

• Added some tests to cover the issue case.
• Drop the old partition's stats meta.
• Added old table ID to the event to avoid abuse of the new table ID from partition info.

Check List

Tests

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

  • I checked and no code files have been changed.

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.

Fix TiDB cannot delete old partition's stats meta after changing partitioned tables to non-partitioned tables

[codecov]

Codecov Report

Merging #49553 (51ab22c) into master (ad1efe4) will increase coverage by 0.4606%.
Report is 1 commits behind head on master.
The diff coverage is 41.3793%.

Additional details and impacted files

@@               Coverage Diff                @@
##             master     #49553        +/-   ##
================================================
+ Coverage   71.0028%   71.4634%   +0.4606%     
================================================
  Files          1368       1421        +53     
  Lines        399204     415727     +16523     
================================================
+ Hits         283446     297093     +13647     
- Misses        95973      99835      +3862     
+ Partials      19785      18799       -986     

Flag	Coverage Δ
integration	43.6561% <41.3793%> (?)
unit	71.0027% <ø> (-0.0001%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
dumpling	53.9663% <ø> (ø)
parser	∅ <ø> (∅)
br	47.3644% <ø> (-5.5178%)	⬇️

[Rustin170506]

🔢 Self-check

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: time-and-fate, zimulala

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• OWNERS [time-and-fate,zimulala]
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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2023-12-19 04:50:49.549100727 +0000 UTC m=+936540.586327653: ☑️ agreed by time-and-fate.
• 2023-12-19 12:15:33.828187246 +0000 UTC m=+963224.865414175: ☑️ agreed by zimulala.