disk_snap_restore: remove checking store number (#51886)

[ti-chi-bot]

This is an automated cherry-pick of #51886

warn if store num not match

What problem does this PR solve?

Issue Number: close #51957

Problem Summary:
It is unnecessary to check the store number in data restore phase -- since tidb-operator will help us to check it.
Now this check breaks a workaround for one store cannot unexpectedly bootstrap after restoring.

What changed and how does it work?

This PR removes the check to number of stores.

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.

  The change is tiny and I manually tested it in a local k8s cluster.

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]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Please upload report for BASE (release-7.5@2ecc47d). Learn more about missing BASE report.

Additional details and impacted files

@@               Coverage Diff                @@
##             release-7.5     #52563   +/-   ##
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  Coverage               ?   71.9903%           
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  Lines                  ?     409434           
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  Hits                   ?     294753           
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Flag	Coverage Δ
unit	71.9903% <ø> (?)

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Components	Coverage Δ
dumpling	53.9913% <0.0000%> (?)
parser	∅ <0.0000%> (?)
br	53.3457% <0.0000%> (?)

[YuJuncen]

should be picked in #53027