refactor: Renamed KeyEventHandler::with to KeyEventHandler::new to keep with Rust best practices and conventions

src/handlers/radarr_handlers/radarr_handler_tests.rs

@@ -222,7 +222,7 @@ mod tests {
     let mut app = App::default();
     app.is_loading = true;
 
-    let handler = RadarrHandler::with(
+    let handler = RadarrHandler::new(
       DEFAULT_KEYBINDINGS.esc.key,
       &mut app,
       ActiveRadarrBlock::System,