DGS-22768 Update FIPS documentation for 140-3 compliance

[kcorman0]

What

FIPS 140-3 (newest) requires a newer openssl version, updating documentation around this. Also went through SR dependencies and believe they're still compliant.

Probably need a +1 from clients team for non-SR aspect of this client as the change implies entire client is 140-3 compliant.

Checklist

• [N] Contains customer facing changes? Including API/behavior changes
• [Y] Did you add sufficient unit test and/or integration test coverage for this PR?
  • If not, please explain why it is not required

References

JIRA:

Test & Review

Open questions / Follow-ups

[confluent-cla-assistant]

🎉 All Contributor License Agreements have been signed. Ready to merge.
_{Please push an empty commit if you would like to re-run the checks to verify CLA status for all contributors.}

[Copilot]

Pull Request Overview

This PR updates FIPS documentation to support FIPS 140-3 compliance by clarifying the differences between FIPS 140-2 and FIPS 140-3, updating OpenSSL version requirements, and providing clearer guidance for new deployments.

• Updated OpenSSL version requirements to support both FIPS 140-2 (OpenSSL 3.0.x) and FIPS 140-3 (OpenSSL 3.1.2+)
• Added recommendation for FIPS 140-3 for new deployments due to upcoming federal procurement requirements
• Updated configuration examples and links to point to the newer OpenSSL version

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[sonarqube-confluent]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
No data about Duplication

See analysis details on SonarQube

[k-raina]

Thanks @kcorman0 for PR!
May i know how did you test this PR with openssl 3.1.2 recommended?