copIterator: return context error to avoid return incorrect result on context cancel/timeout (#53489)

[ti-chi-bot]

This is an automated cherry-pick of #53489

What problem does this PR solve?

Issue Number: close #50089 #55500

Problem Summary:

What changed and how does it work?

always return context error when recvFromRespCh return closed=true

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

Attention: Patch coverage is 72.72727% with 3 lines in your changes missing coverage. Please review.

Please upload report for BASE (release-7.5@47279f5). Learn more about missing BASE report.

Additional details and impacted files

@@               Coverage Diff                @@
##             release-7.5     #55638   +/-   ##
================================================
  Coverage               ?   72.0003%           
================================================
  Files                  ?       1413           
  Lines                  ?     411877           
  Branches               ?          0           
================================================
  Hits                   ?     296553           
  Misses                 ?      95426           
  Partials               ?      19898           

Flag	Coverage Δ
unit	72.0003% <72.7272%> (?)

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	53.5059% <0.0000%> (?)

[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2024-09-14 04:15:40.151607616 +0000 UTC m=+675409.892031550: ☑️ agreed by D3Hunter.
• 2024-09-14 05:57:06.427046505 +0000 UTC m=+681496.167470467: ☑️ agreed by joccau.

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

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

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