[DS] add deprecation comment to `ApiActionDirective` (#10041)

libs/angular/src/directives/api-action.directive.ts

@@ -9,6 +9,8 @@ import { ValidationService } from "@bitwarden/common/platform/abstractions/valid
  * Attach it to a <form> element and provide the name of the class property that will hold the api call promise.
  * e.g. <form [appApiAction]="this.formPromise">
  * Any errors/rejections that occur will be intercepted and displayed as error toasts.
+ *
+ * @deprecated Use the CL's {@link BitSubmitDirective} instead
  */
 @Directive({
   selector: "[appApiAction]",