Add in required capabilities for writing TLS secrets

[ciarams87]

Proposed changes

Problem: TLS termination is not working because the NGINX container is missing the DAC_OVERRIDE capability. This is required to bypass write permission checks on the files in /etc/nginx/secrets so we can write the TLS secrets to disk.

Solution: Explain the approach you took to implement the solution, highlighting any significant design decisions or
considerations.

Closes #714

Checklist

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• 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