docs(material/autocomplete): change documentation for the optionActivated event (#24844)

Fixes #24799

(cherry picked from commit 6266270)

Author: ddubrava

src/material/autocomplete/autocomplete.ts

@@ -172,7 +172,7 @@ export abstract class _MatAutocompleteBase
   /** Event that is emitted when the autocomplete panel is closed. */
   @Output() readonly closed: EventEmitter<void> = new EventEmitter<void>();
 
-  /** Emits whenever an option is activated using the keyboard. */
+  /** Emits whenever an option is activated. */
   @Output() readonly optionActivated: EventEmitter<MatAutocompleteActivatedEvent> =
     new EventEmitter<MatAutocompleteActivatedEvent>();