fix: restore shard cluster failed if the origin cluster's shards less than cluster's shards

[wangyelei]

No description provided.

[apecloud-bot]

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[codecov]

Codecov Report

❌ Patch coverage is 0% with 4 lines in your changes missing coverage. Please review.
✅ Project coverage is 53.92%. Comparing base (16f2a67) to head (a6cd830).
⚠️ Report is 2 commits behind head on release-1.0.

Files with missing lines	Patch %	Lines
...ollers/apps/cluster/transformer_cluster_restore.go	0.00%	4 Missing ⚠️

Additional details and impacted files

@@               Coverage Diff               @@
##           release-1.0   #10023      +/-   ##
===============================================
+ Coverage        53.79%   53.92%   +0.13%     
===============================================
  Files              493      493              
  Lines            54746    54750       +4     
===============================================
+ Hits             29449    29525      +76     
+ Misses           22362    22302      -60     
+ Partials          2935     2923      -12     

Flag	Coverage Δ
unittests	53.92% <0.00%> (+0.13%)	⬆️

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