Update NGINX and NGINX Agent (#3737)

[sjberman]

Updating NGINX to 1.29.1 and NGINX Agent to 3.2.1

Checklist

Before creating a PR, run through this checklist and mark each as complete.

• I have read the CONTRIBUTING doc
• I have added tests that prove my fix is effective or that my feature works
• I have checked that all unit tests pass after adding my changes
• I have updated necessary documentation
• I have rebased my branch onto main
• I will ensure my PR is targeting the main branch and pulling from my branch from my own fork

Release notes

If this PR introduces a change that affects users and needs to be mentioned in the release notes,
please add a brief note that summarizes the change.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 86.96%. Comparing base (fd94860) to head (9bb949a).
⚠️ Report is 1 commits behind head on release-2.1.

Additional details and impacted files

@@ Coverage Diff @@ ## release-2.1 #3738 +/- ## ============================================ Coverage 86.96% 86.96% ============================================ Files 128 128 Lines 15986 15986 Branches 62 62 ============================================ Hits 13902 13902 Misses 1918 1918 Partials 166 166 

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