NGINX Plus FIPS Compliance

[y82]

Proposed changes

This is a major rework of https://docs.nginx.com/nginx/fips-compliance-nginx-plus/, in particular:

• FIPS 140-3 compliance
• rewritten procedures acc. to rhel 9 and openssl3
• intro added
• fips complaint vs fips validated added
• list of industries and countries added
• list of nist certificates updated

work that still in progress:

• some sample/test command specific for FIPS140-3
• algs comparison FIPS140-2 vs FIPS140-3

Testing:
RHEL 9
Ubuntu 24.04 (not fips3 certified)
Ubuntu 22.04 (FIPS3 certified)

Reviewing hint: I'd suggest reviewing "from scratch" and ignore the diff - it was heavily rewritten

Checklist

Before sharing this pull request, I completed the following checklist:

• I read the Contributing guidelines
• My branch adheres to the Git conventions
• My content changes adhere to the F5 NGINX Documentation style guide
• If my changes involve potentially sensitive information¹, I have assessed the possible impact
• I have waited to ensure my changes pass tests, and addressed any discovered issues

Footnotes

1. Potentially sensitive information includes personally identify information (PII), authentication credentials, and live URLs. Refer to the style guide for guidance about placeholder content. ↩