Add repository maintenance job configuration design.

[blackpiglet]

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Fixes #(issue)
Design for #7758

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 58.82%. Comparing base (84feddb) to head (d72f857).
Report is 2 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #8009   +/-   ##
=======================================
  Coverage   58.82%   58.82%           
=======================================
  Files         346      346           
  Lines       28892    28892           
=======================================
  Hits        16995    16995           
  Misses      10468    10468           
  Partials     1429     1429           

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[blackpiglet]

Change the way to get the new ConfigMap from name to label.