[gitlab] replace docker tag calls for k8s runners

[celenechang]

What does this PR do?

The migration from docker runners to k8s runners in #1056 was incomplete, this fixes the remaining docker tag calls.

Motivation

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Additional Notes

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Minimum Agent Versions

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• Agent: vX.Y.Z
• Cluster Agent: vX.Y.Z

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Checklist

• PR has at least one valid label: bug, enhancement, refactoring, documentation, tooling, and/or dependencies
• PR has a milestone or the qa/skip-qa label

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 58.93%. Comparing base (703a0e2) to head (8b2f306).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1103   +/-   ##
=======================================
  Coverage   58.93%   58.93%           
=======================================
  Files         174      174           
  Lines       21357    21357           
=======================================
  Hits        12587    12587           
  Misses       8004     8004           
  Partials      766      766           

Flag	Coverage Δ
unittests	58.93% <ø> (ø)

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