Bump agent image versions to 7.55.1

[sblumenthal]

What does this PR do?

Bump agent image versions to 7.55.1

Motivation

7.55.1 was just released

Additional Notes

Minimum Agent Versions

Describe your test plan

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 55.04%. Comparing base (247d5e5) to head (4c8b3f1).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1290   +/-   ##
=======================================
  Coverage   55.04%   55.04%           
=======================================
  Files         244      244           
  Lines       28167    28167           
=======================================
  Hits        15504    15504           
  Misses      11785    11785           
  Partials      878      878           

Flag	Coverage Δ
unittests	55.04% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Files	Coverage Δ
pkg/defaulting/images.go	100.00% <ø> (ø)

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[celenechang]

closing, duplicate of #1287