ddl: fix taskNodes temporarily

[xhebox]

Signed-off-by: xhe xw897002528@gmail.com<!--

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What problem does this PR solve?

Issue Number: ref #46258

Problem Summary: When dispatcher fails, the new dispatcher will pick up the running task while not invoking onNextStage. In this case, we need to fallback to task table for taskNodes.

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

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None

[tiprow]

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[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

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

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2023-09-05 07:26:24.055339958 +0000 UTC m=+2430348.604355929: ☑️ agreed by tangenta.
• 2023-09-05 07:29:31.882028821 +0000 UTC m=+2430536.431044808: ☑️ agreed by ywqzzy.

[codecov]

Codecov Report

Merging #46671 (3346e95) into master (db570ea) will decrease coverage by 0.8337%.
Report is 6 commits behind head on master.
The diff coverage is 0.0000%.

Additional details and impacted files

@@               Coverage Diff                @@
##             master     #46671        +/-   ##
================================================
- Coverage   73.3586%   72.5250%   -0.8337%     
================================================
  Files          1315       1336        +21     
  Lines        395675     403524      +7849     
================================================
+ Hits         290262     292656      +2394     
- Misses        86932      92247      +5315     
- Partials      18481      18621       +140     

Flag	Coverage Δ
integration	25.4076% <0.0000%> (?)
unit	73.3508% <0.0000%> (-0.0079%)	⬇️

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

Components	Coverage Δ
dumpling	54.0444% <ø> (ø)
parser	84.9689% <ø> (+0.0108%)	⬆️
br	48.1092% <ø> (-4.3283%)	⬇️

[xhebox]

/retest

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