Support using image registry proxy in more cases.

[blackpiglet]

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Fixes #(issue)

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 59.56%. Comparing base (d5a2e7e) to head (14e1055).
Report is 2 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #8927   +/-   ##
=======================================
  Coverage   59.56%   59.56%           
=======================================
  Files         370      370           
  Lines       40267    40267           
=======================================
  Hits        23987    23987           
  Misses      14778    14778           
  Partials     1502     1502           

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[kaovilai]

lgtm.

Notes

The removal of the useVolumeSnapshots parameter from the KibishiiPrepareBeforeBackup and installKibishii functions doesn't affect the functionality because:

1. The parameter wasn't actually used within those functions.
2. The parameter is still used in the RunKibishiiTests function where it's needed for the backup configuration and post-backup verification.