fix: shallow copy response to avoid data race

[jayantxie]

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fix

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[codecov]

Codecov Report

❌ Patch coverage is 94.44444% with 3 lines in your changes missing coverage. Please review.
✅ Project coverage is 60.21%. Comparing base (4cfae2c) to head (8efbad4).

Files with missing lines	Patch %	Lines
pkg/retry/util.go	83.33%	2 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1799      +/-   ##
==========================================
- Coverage   60.26%   60.21%   -0.06%     
==========================================
  Files         381      381              
  Lines       34514    34483      -31     
==========================================
- Hits        20799    20763      -36     
- Misses      12450    12455       +5     
  Partials     1265     1265              

Flag	Coverage Δ
integration	48.61% <83.33%> (+<0.01%)	⬆️
unit	50.78% <92.59%> (-0.07%)	⬇️

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[xiaost]

TypeOf 可以简单点。还不用判断 Nil