local backend: fix log been eaten when failed on execute region job (#47782)

[ti-chi-bot]

This is an automated cherry-pick of #47782

What problem does this PR solve?

Issue Number: close #47781

Problem Summary:

What is changed and how it works?

log error of worker waitgroup if it's not context cancelled

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
  temporary change code, send a dummy job in generateAndSendJob then wait 5 second, and let executeJob always return the remaining storage capacity of TiKV error, see we can see the eaten log

[2023/10/19 16:01:56.812 +08:00] [ERROR] [local.go:1677] ["worker meets error"] [error="the remaining storage capacity of TiKV(%!s(MISSING)) is less than 10%; please increase the storage capacity of TiKV
and try again"] [errorVerbose="the remaining storage capacity of TiKV(%!s(MISSING)) is less than 10%; please increase the storage capacity of TiKV and try again\ngithub.com/pingcap/tidb/br/pkg/lightning/b
ackend/local.(*Backend).executeJob\n\t/Users/jujiajia/code/pingcap/tidb/br/pkg/lightning/backend/local/local.go:1405\ngithub.com/pingcap/tidb/br/pkg/lightning/backend/local.(*Backend).startWorker\n\t/Users/jujiajia/code/pingcap/tidb/br/pkg/lightning/backend/local/local.go:1340\ngithub.com/pingcap/tidb/br/pkg/lightning/backend/local.(*Backend).doImport.func5\n\t/Users/jujiajia/code/pingcap/tidb/br/pkg/lightning/backend/local/local.go:1657\ngolang.org/x/sync/errgroup.(*Group).Go.func1\n\t/Users/jujiajia/go/pkg/mod/golang.org/x/sync@v0.3.0/errgroup/errgroup.go:75\nruntime.goexit\n\t/usr/local/go/src/runtime/asm_arm64.s:1197"]

• 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

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: D3Hunter, lance6716

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• br/pkg/lightning/OWNERS [D3Hunter,lance6716]

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2023-10-20 02:14:40.979385029 +0000 UTC m=+1968878.566495175: ☑️ agreed by D3Hunter.
• 2023-10-20 02:17:37.515691259 +0000 UTC m=+1969055.102801404: ☑️ agreed by lance6716.

[D3Hunter]

/retest