Add schannel feature

[masa-koz]

Description

This pull request introduces support for the schannel feature and updates the build configuration accordingly. The most important changes include modifying the GitHub Actions workflow, updating the Cargo.toml file, and adjusting the build script to conditionally define the TLS library.

Support for schannel feature:

• .github/workflows/cargo.yml: Expanded the features matrix to include --features schannel and --features schannel,static, and excluded incompatible combinations for certain operating systems.
• Cargo.toml: Added a new feature named schannel to the features list.

Build configuration adjustments:

• scripts/build.rs: Modified the build script to conditionally define the QUIC_TLS library based on the presence of the schannel feature, defaulting to openssl if not specified.

Testing

• cargo test --features schannel
• cargo test --features schannel,static

Documentation

TBD

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 86.68%. Comparing base (f16a46b) to head (7d7b034).
Report is 4 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4735      +/-   ##
==========================================
- Coverage   87.20%   86.68%   -0.52%     
==========================================
  Files          56       56              
  Lines       17363    17363              
==========================================
- Hits        15141    15051      -90     
- Misses       2222     2312      +90     

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