chore: remove unused variables in GenerateManifests

[Abirdcfly]

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[codecov]

Codecov Report

Patch coverage: 100.00% and no project coverage change.

Comparison is base (ec2340a) 49.48% compared to head (9776af4) 49.48%.

Additional details and impacted files

@@           Coverage Diff           @@
##           master   #13887   +/-   ##
=======================================
  Coverage   49.48%   49.48%           
=======================================
  Files         256      256           
  Lines       43847    43841    -6     
=======================================
- Hits        21697    21695    -2     
+ Misses      19988    19985    -3     
+ Partials     2162     2161    -1     

Impacted Files	Coverage Δ
reposerver/repository/repository.go	60.72% <100.00%> (+0.08%)	⬆️

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