Openssl testing version strategy

[dougch]

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Problem:

As pointed out in #4992, we're pinned to OpenSSL 3.0.0 for testing.
OpenSSL 3.1-3.4 are also available, but we need to pay attention to OpenSSL's LTS guidance:

Version 3.3 will be supported until 2026-04-09
Version 3.2 will be supported until 2025-11-23
Version 3.1 will be supported until 2025-03-14
Version 3.0 will be supported until 2026-09-07 (LTS).

see https://openssl-library.org/policies/releasestrat/index.html

Solution:

3.0.0 is the designated LTS release, and arguably, 3.1 and 3.2 are close enough to EOS we should consider skipping.

More discussion is needed, but based on above, we should add testing of 3.3 and 3.4 (no listed EOS).

Requirements / Acceptance Criteria:

What must a solution address in order to solve the problem? How do we know the solution is complete?

• RFC links: Links to relevant RFC(s)
• Related Issues: Link any relevant issues
• Will the Usage Guide or other documentation need to be updated?
• Testing: How will this change be tested? Call out new integration tests, functional tests, or particularly interesting/important unit tests.
  • Will this change trigger SAW changes? Changes to the state machine, the s2n_handshake_io code that controls state transitions, the DRBG, or the corking/uncorking logic could trigger SAW failures.
  • Should this change be fuzz tested? Will it handle untrusted input? Create a separate issue to track the fuzzing work.

Out of scope:

Is there anything the solution will intentionally NOT address?

[lrstewart]

We should support Openssl 3.0 (LTS) and the latest Openssl (currently 3.4)