Create an StorageRecorder interface to fix unexported-return

[aladesawe]

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[k8s-ci-robot]

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[k8s-ci-robot]

Hi @aladesawe. Thanks for your PR.

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[aladesawe]

Pulled from PR

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 68.82%. Comparing base (92673d1) to head (cc79a88).
Report is 165 commits behind head on main.

Additional details and impacted files

Files with missing lines	Coverage Δ
server/mock/mockstorage/storage_recorder.go	95.00% <100.00%> (ø)

... and 53 files with indirect coverage changes

@@            Coverage Diff             @@
##             main   #19341      +/-   ##
==========================================
+ Coverage   68.79%   68.82%   +0.03%     
==========================================
  Files         420      420              
  Lines       35629    35716      +87     
==========================================
+ Hits        24510    24583      +73     
- Misses       9700     9708       +8     
- Partials     1419     1425       +6     

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[ahrtr]

An alternative & simpler solution is to rename storageRecorder to StorageRecorder.