Removed commentImprovements labs flag

closes https://linear.app/ghost/issue/PLG-300

- we're not planning on making any more comments improvements behind this flag so it can be removed
- all conditionals using it have been cleaned up previously when feature went GA

apps/admin-x-settings/src/components/settings/advanced/labs/AlphaFeatures.tsx

@@ -47,10 +47,6 @@ const features = [{
     title: 'Content Visibility',
     description: 'Enables content visibility in Emails',
     flag: 'contentVisibility'
-}, {
-    title: 'Comment Improvements',
-    description: 'Enables new comment features',
-    flag: 'commentImprovements'
 }, {
     title: 'Post analytics redesign',
     description: 'Enables redesigned Post analytics page',

ghost/admin/app/services/feature.js

@@ -75,7 +75,6 @@ export default class FeatureService extends Service {
     @feature('ActivityPub') ActivityPub;
     @feature('editorExcerpt') editorExcerpt;
     @feature('contentVisibility') contentVisibility;
-    @feature('commentImprovements') commentImprovements;
     @feature('postsX') postsX;
 
     _user = null;

ghost/core/core/shared/labs.js

@@ -52,7 +52,6 @@ const ALPHA_FEATURES = [
     'collectionsCard',
     'lexicalIndicators',
     'adminXDemo',
-    'commentImprovements',
     'postsX'
 ];
 

ghost/core/test/e2e-api/admin/__snapshots__/config.test.js.snap

@@ -17,7 +17,6 @@ Object {
       "audienceFeedback": true,
       "collections": true,
       "collectionsCard": true,
-      "commentImprovements": true,
       "contentVisibility": true,
       "customFonts": true,
       "editorExcerpt": true,