Refactor and Enhance Compression Field Testing

Refactor and Enhance Compression Field Testing

Fixes #7940: Enhances the existing test for compression methods in the ClientHello message, aligning with RFC 8446 specifications.

Refactored the test code to improve modularity and maintainability, making it easier to extend and modify in the future.

Added checks for the appropriate alerts, ensuring that `SSL_AD_ILLEGAL_PARAMETER` or `SSL_AD_DECODE_ERROR` are correctly triggered as per the RFC 8446 guidelines.

Expanded Test Coverage: Introduced additional test cases to cover scenarios involving:
- Lists of unknown compression methods
- Absence of any compression method
- Validation of a single null compression method, which should always succeed.

Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/25255)