feat(client): Remove cross-origin redirect proxy support

[0x676e67]

This pull request involves the removal of the redirect_with_proxy_auth feature from the HTTP client in the src/client/http.rs file. The changes simplify the codebase by removing associated configurations, methods, and references to this feature.

Key changes include:

Removal of redirect_with_proxy_auth feature:

• src/client/http.rs: Removed the redirect_with_proxy_auth field from the Config and ClientInner structs. [1] [2]
• src/client/http.rs: Deleted the redirect_with_proxy_auth method from the ClientBuilder implementation.
• src/client/http.rs: Removed references to redirect_with_proxy_auth from the ClientBuilder and PendingRequest implementations. [1] [2] [3]

Update to header removal logic:

• src/redirect.rs: Simplified the remove_sensitive_headers method by removing the cross_proxy_auth parameter and its associated logic.

Tests update:

• src/redirect.rs: Updated the test_remove_sensitive_headers test to reflect the changes in the remove_sensitive_headers method and removed the test_proxy_auth_redirect_headers test.