perf(connector): Optimize performance of switching TLS connector

[0x676e67]

This pull request includes several changes to the src/connect.rs and src/client/http.rs files, focusing on simplifying the ConnectorBuilder and Connector implementations, removing unused imports, and refactoring the handling of TLS connectors.

Refactoring and simplification:

• src/client/http.rs: Simplified the ConnectorBuilder construction by chaining method calls instead of using intermediate variables.
• src/connect.rs: Refactored the ConnectorBuilder methods (set_keepalive, set_timeout, set_verbose) to return self for method chaining.
• src/connect.rs: Removed the InnerTLS enum and replaced it with a simpler direct use of BoringTlsConnector.

Code cleanup:

• src/connect.rs: Removed unused imports (antidote::RwLock and std::sync::Arc). [1] [2]

Improved Connector handling:

• src/connect.rs: Updated the Connector::WithLayers variant to include layers and base_service, and refactored the set_connector method to rebuild the connector with the new TLS settings. [1] [2] [3]