fix: runs git lfs install --system that writes the following to /etc/gitconfig

[ppapapetrou76]

The issue is caused because the latest base OS image used ( ubuntu:25.10 ) is not creating the file

Runs git lfs install --system that writes the following to /etc/gitconfig inside Docker file
This is creating the missing /etc/config

closes #27956

Checklist:

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[bunnyshell]

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 64.36%. Comparing base (f7ea5bc) to head (efcb87c).

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #27961      +/-   ##
==========================================
- Coverage   64.39%   64.36%   -0.04%     
==========================================
  Files         422      422              
  Lines       57829    57829              
==========================================
- Hits        37239    37221      -18     
- Misses      17089    17106      +17     
- Partials     3501     3502       +1     

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[argo-cd-cherry-pick-bot]

🍒 Cherry-pick PR created for 3.4: #27972