fix dry run creation time

[wy65701436]

Give the mock time for dry run, otherwise, it will be zero.

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Comprehensive Summary of your change

Issue being fixed

Fixes #(issue)

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[codecov]

Codecov Report

Merging #19060 (d577b2c) into main (bef4ccc) will decrease coverage by 0.01%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##             main   #19060      +/-   ##
==========================================
- Coverage   67.42%   67.41%   -0.01%     
==========================================
  Files         992      992              
  Lines      108738   108739       +1     
  Branches     2748     2748              
==========================================
- Hits        73312    73303       -9     
- Misses      31494    31504      +10     
  Partials     3932     3932              

Flag	Coverage Δ
unittests	67.41% <0.00%> (-0.01%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files Changed	Coverage Δ
src/jobservice/job/impl/gc/garbage_collection.go	45.95% <0.00%> (-0.10%)	⬇️

... and 6 files with indirect coverage changes

[AllForNothing]

lgtm

[chlins]

lgtm