ebs br: rename a tag for EBS snapshots (#50870)

[ti-chi-bot]

This is an automated cherry-pick of #50870

What problem does this PR solve?

Issue Number: close #50878

Problem Summary:

What changed and how does it work?

This PR is to address a name duplication issue doing backup from a restored cluster. The tag key of snapshots is renamed from TiDBCluster-BR to TiDBCluster-BR-Snapshot

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

❗ No coverage uploaded for pull request base (release-6.5@44f39e9). Click here to learn what that means.
The diff coverage is 0.0000%.

Additional details and impacted files

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##             release-6.5     #50897   +/-   ##
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[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: BornChanger, Leavrth

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• OWNERS [Leavrth]

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2024-02-03 12:22:59.616744153 +0000 UTC m=+13905.183514028: ☑️ agreed by BornChanger.
• 2024-02-26 03:34:15.379960479 +0000 UTC m=+846544.127583587: ☑️ agreed by Leavrth.