ttl: fix some memory leak in TTL (#56935)

[ti-chi-bot]

This is an automated cherry-pick of #56935

What problem does this PR solve?

Issue Number: close #56934

What changed and how does it work?

fix some memory leaks in TTL

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)

Create 1000 TTL tables with ttl_job_interval='1m' to see the memory usage:

• 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.

None

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Please upload report for BASE (release-8.4@12a4ea9). Learn more about missing BASE report.

Additional details and impacted files

@@               Coverage Diff                @@
##             release-8.4     #56952   +/-   ##
================================================
  Coverage               ?   56.2104%           
================================================
  Files                  ?       1752           
  Lines                  ?     628182           
  Branches               ?          0           
================================================
  Hits                   ?     353104           
  Misses                 ?     251161           
  Partials               ?      23917           

Flag	Coverage Δ
integration	36.8158% <50.0000%> (?)
unit	72.4774% <100.0000%> (?)

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

Components	Coverage Δ
dumpling	52.9478% <0.0000%> (?)
parser	∅ <0.0000%> (?)
br	52.4162% <0.0000%> (?)

[lcwangchao]

/retest

[YangKeao]

LGTM

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: lcwangchao, YangKeao

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• OWNERS [YangKeao,lcwangchao]

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2024-10-29 09:54:05.377802699 +0000 UTC m=+343558.216958240: ☑️ agreed by lcwangchao.
• 2024-10-29 10:36:13.155702609 +0000 UTC m=+346085.994858155: ☑️ agreed by YangKeao.

[lcwangchao]

/retest