[AGENTRUN-1051] Update FIPS proxy version references to 1.1.21

[louis-cqrl]

What does this PR do?

Update FIPS proxy version references to 1.1.21

Motivation

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Additional Notes

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Minimum Agent Versions

Are there minimum versions of the Datadog Agent and/or Cluster Agent required?

• 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
• All commits are signed (see: signing commits)

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 38.29%. Comparing base (f391e33) to head (d587e5a).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2628   +/-   ##
=======================================
  Coverage   38.29%   38.29%           
=======================================
  Files         305      305           
  Lines       26301    26301           
=======================================
  Hits        10073    10073           
  Misses      15463    15463           
  Partials      765      765           

Flag	Coverage Δ
unittests	38.29% <ø> (ø)

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

Files with missing lines	Coverage Δ
pkg/images/images.go	95.27% <ø> (ø)

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