br: remove timeout context to scan regions when import sst files (#53739)

[ti-chi-bot]

This is an automated cherry-pick of #53739

What problem does this PR solve?

Issue Number: close #53724

Problem Summary:
only 10 seconds to retry scan regions

What changed and how does it work?

remove timeout context to scan regions when import sst files

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

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: 3pointer, Leavrth

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• OWNERS [3pointer,Leavrth]

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2024-06-06 08:35:11.699616923 +0000 UTC m=+21665.752928846: ☑️ agreed by Leavrth.
• 2024-06-06 08:47:25.533768473 +0000 UTC m=+22399.587080394: ☑️ agreed by 3pointer.

[codecov]

Codecov Report

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Additional details and impacted files

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