set tag pull time for proxy cache

[wy65701436]

fixes #18708

to set the pull time of tag for the first time cache the artifact.

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Comprehensive Summary of your change

Issue being fixed

Fixes #(issue)

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[codecov]

Codecov Report

Merging #18742 (bae9362) into release-2.7.0 (7a0f0ea) will increase coverage by 22.46%.
The diff coverage is 30.00%.

@@                Coverage Diff                 @@
##           release-2.7.0   #18742       +/-   ##
==================================================
+ Coverage          43.95%   66.41%   +22.46%     
==================================================
  Files                245     1012      +767     
  Lines              13396   108643    +95247     
  Branches            2677     2677               
==================================================
+ Hits                5888    72154    +66266     
- Misses              7222    32520    +25298     
- Partials             286     3969     +3683     

Flag	Coverage Δ
unittests	66.41% <30.00%> (+22.46%)	⬆️

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

Impacted Files	Coverage Δ
src/controller/artifact/controller.go	63.13% <0.00%> (ø)
src/controller/proxy/controller.go	14.91% <0.00%> (ø)
src/controller/tag/controller.go	72.14% <66.66%> (ø)

... and 767 files with indirect coverage changes

[chlins]

lgtm

[chlins]

lgtm