chore(cleanup): editor singleton

It is not needed anymore now that the editor is always imported from text.

Previously the ViewerComponent was used directly from the viewer
which resulted in the editor and thus yjs being imported in two different ways.

Signed-off-by: Max <max@nextcloud.com>

Author: max-nextcloud

src/components/Editor.singleton.js

@@ -27,14 +27,14 @@
 <script>
 import { getSharingToken } from '@nextcloud/sharing/public'
 import { defineComponent } from 'vue'
-import getEditorInstance from './Editor.singleton.js'
+import Editor from './Editor.vue'
 import SourceView from './SourceView.vue'
 
 export default defineComponent({
 	name: 'ViewerComponent',
 	components: {
 		SourceView,
-		Editor: getEditorInstance,
+		Editor,
 	},
 	provide() {
 		return {

src/components/ViewerComponent.vue

@@ -37,7 +37,7 @@ import { t } from '@nextcloud/l10n'
 import { generateOcsUrl } from '@nextcloud/router'
 import { getSharingToken, isPublicShare } from '@nextcloud/sharing/public'
 
-import getEditorInstance from '../components/Editor.singleton.js'
+import Editor from '../components/Editor.vue'
 import RichTextReader from '../components/RichTextReader.vue'
 
 const IS_PUBLIC = isPublicShare()
@@ -58,7 +58,7 @@ export default {
 	name: 'RichWorkspace',
 	components: {
 		RichTextReader,
-		Editor: getEditorInstance,
+		Editor,
 	},
 	props: {
 		content: {