chore: cleanup standalone flag

Author: sibiraj-s

projects/ngx-tiptap/src/lib/bubble-menu.directive.ts

@@ -7,7 +7,6 @@ import { BubbleMenuPlugin, BubbleMenuPluginProps } from '@tiptap/extension-bubbl
 
 @Directive({
   selector: 'tiptap-bubble-menu[editor], [tiptapBubbleMenu][editor]',
-  standalone: true,
 })
 export class TiptapBubbleMenuDirective implements OnInit, OnDestroy {
   private elRef = inject<ElementRef<HTMLElement>>(ElementRef);