comment dont have default placeholder (microsoft#234105)

Fixes microsoft#234060

Author: alexr00

src/vs/workbench/contrib/comments/browser/simpleCommentEditor.ts

@@ -38,6 +38,7 @@ import { SelectionClipboardContributionID } from '../../codeEditor/browser/selec
 import { MenuId } from '../../../../platform/actions/common/actions.js';
 import { ContentHoverController } from '../../../../editor/contrib/hover/browser/contentHoverController.js';
 import { GlyphHoverController } from '../../../../editor/contrib/hover/browser/glyphHoverController.js';
+import { PlaceholderTextContribution } from '../../../../editor/contrib/placeholderText/browser/placeholderTextContribution.js';
 
 export const ctxCommentEditorFocused = new RawContextKey<boolean>('commentEditorFocused', false);
 export const MIN_EDITOR_HEIGHT = 5 * 18;
@@ -84,6 +85,7 @@ export class SimpleCommentEditor extends CodeEditorWidget {
 					SelectionClipboardContributionID,
 					InlineCompletionsController.ID,
 					CodeActionController.ID,
+					PlaceholderTextContribution.ID
 				])
 			],
 			contextMenuId: MenuId.SimpleEditorContext