Use Docker Hub mirror registry to avoid hitting the pull limit

[codecov[bot]]

Codecov Report

Merging #516 (b35ceec) into main (157f011) will not change coverage. The diff coverage is n/a.

:exclamation: Current head b35ceec differs from pull request most recent head a4d98ad. Consider uploading reports for the commit a4d98ad to get more accurate results

@@            Coverage Diff            @@
##               main     #516   +/-   ##
=========================================
  Coverage     69.92%   69.92%           
  Complexity      739      739           
=========================================
  Files            63       63           
  Lines          4802     4802           
  Branches        530      530           
=========================================
  Hits           3358     3358           
  Misses         1165     1165           
  Partials        279      279           

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[daniele-moro]

~Increase a lot the time in CI, because it always rebuild the tester image container, since it's not able to use cache. Need to revise that.~

[daniele-moro]

Build with buildkit using cached images has been restored, so time are back to normal, but now we use the dockerhub mirror.

[daniele-moro]

retest this please