Update permissions of gateway binary for UBI

[shaun-nx]

Proposed changes

This change ensures that the gateway binary that we copy to /usr/bin/gateway in our UBI Control Plane Dockerfile has the appropriate permissions to run.

Currently, this causes an error in our UBI deployments that prevents the certificate generator pod from running.

Closes #4405

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.

Fix permission issue with nginx-gateway container for UBI 

[sjberman]

Can you create an issue associated with this?

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 86.12%. Comparing base (c2a4813) to head (32c4f80).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #4404   +/-   ##
=======================================
  Coverage   86.12%   86.12%           
=======================================
  Files         132      132           
  Lines       14381    14381           
  Branches       35       35           
=======================================
  Hits        12386    12386           
  Misses       1785     1785           
  Partials      210      210           

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[sjberman]

Also, in the release note, I'd update this to say nginx-gateway container, because the same binary is used for both the cert-generator job and the main controller.