refactor: Replace unsafe methods with safe methods in ConnectConfiguration

[0x676e67]

This pull request includes several updates and refactorings to the Cargo.toml and src/tls files. The main changes involve updating dependencies and refactoring the code to remove unsafe blocks and improve readability.

Dependency Updates:

• Cargo.toml: Updated the boring2, boring-sys2, and tokio-boring2 dependencies from version 4.15.0 to 4.15.1.

Code Refactoring:

• src/tls/ext.rs: Added SslOptions to the import statement from boring2::ssl.
• src/tls/ext.rs: Refactored the enable_ech_grease method to remove the unsafe block and use the set_enable_ech_grease method directly.
• src/tls/ext.rs: Refactored the add_application_settings method to remove the unsafe block and use the set_alps_use_new_codepoint method directly.
• src/tls/ext.rs: Refactored the skip_session_ticket method to remove the unsafe block and use the set_options method with SslOptions::NO_TICKET.

Removal of Unused Methods:

• src/tls/mod.rs: Removed the as_ptr and len methods from the AlpsProtos implementation as they are no longer needed.