ddl: handle context done after sending DDL jobs (#57945)

[ti-chi-bot]

This is an automated cherry-pick of #57945

What problem does this PR solve?

Issue Number: close #57863

Problem Summary:

See #57863 (comment)

What changed and how does it work?

The DDL executor should handle the "context is done" case.

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.

None

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Please upload report for BASE (release-7.5@3cd6e2a). Learn more about missing BASE report.

Additional details and impacted files

@@               Coverage Diff                @@
##             release-7.5     #58097   +/-   ##
================================================
  Coverage               ?   72.2448%           
================================================
  Files                  ?       1416           
  Lines                  ?     413476           
  Branches               ?          0           
================================================
  Hits                   ?     298715           
  Misses                 ?      94807           
  Partials               ?      19954           

Flag	Coverage Δ
unit	72.2448% <100.0000%> (?)

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

Components	Coverage Δ
dumpling	52.9400% <0.0000%> (?)
parser	∅ <0.0000%> (?)
br	53.7231% <0.0000%> (?)

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: D3Hunter, tangenta

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• pkg/ddl/OWNERS [tangenta]

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2024-12-12 03:52:44.845820715 +0000 UTC m=+496954.934623258: ☑️ agreed by tangenta.
• 2024-12-12 06:19:43.678452429 +0000 UTC m=+505773.767254972: ☑️ agreed by D3Hunter.

[tangenta]

/retest

[D3Hunter]

/retest