Fixed "About Ghost" missing system information

- the template code had moved to a model in Settings but the controller code
  hadn't been moved over so the getters were missing
- this moves all the relevant code from What's New to the About modal

ghost/admin/app/components/modals/settings/about.js

@@ -12,4 +12,43 @@ export default class AboutModal extends Component {
             this.isTesting = config.environment === 'test';
         }
     }
+
+    get copyrightYear() {
+        const date = new Date();
+        return date.getFullYear();
+    }
+
+    get linkToGitHubReleases() {
+        // Don't link to GitHub Releases if the version contains the
+        // pre-release identifier
+        return !this.config.get('version').includes('-pre.');
+    }
+
+    get showSystemInfo() {
+        const isPro = !!this.config.get('hostSettings')?.siteId;
+
+        // Don't show any system info for Pro
+        if (isPro) {
+            return false;
+        }
+
+        return true;
+    }
+
+    get showDatabaseWarning() {
+        const isProduction = !!this.config.get('environment').match?.(/production/i);
+        const database = this.config.get('database');
+
+        // Show a warning if we're in production and not using MySQL 8
+        if (isProduction && database !== 'mysql8') {
+            return true;
+        }
+
+        // Show a warning if we're in development and using MySQL 5
+        if (!isProduction && database === 'mysql5') {
+            return true;
+        }
+
+        return false;
+    }
 }

ghost/admin/app/controllers/whatsnew.js

@@ -2,48 +2,5 @@ import Controller from '@ember/controller';
 import {inject as service} from '@ember/service';
 
 export default class WhatsNewController extends Controller {
-    @service config;
-    @service upgradeStatus;
     @service whatsNew;
-
-    queryParams = ['entry'];
-
-    get copyrightYear() {
-        const date = new Date();
-        return date.getFullYear();
-    }
-
-    get linkToGitHubReleases() {
-        // Don't link to GitHub Releases if the version contains the
-        // pre-release identifier
-        return !this.config.get('version').includes('-pre.');
-    }
-
-    get showSystemInfo() {
-        const isPro = !!this.config.get('hostSettings')?.siteId;
-
-        // Don't show any system info for Pro
-        if (isPro) {
-            return false;
-        }
-
-        return true;
-    }
-
-    get showDatabaseWarning() {
-        const isProduction = !!this.config.get('environment').match?.(/production/i);
-        const database = this.config.get('database');
-
-        // Show a warning if we're in production and not using MySQL 8
-        if (isProduction && database !== 'mysql8') {
-            return true;
-        }
-
-        // Show a warning if we're in development and using MySQL 5
-        if (!isProduction && database === 'mysql5') {
-            return true;
-        }
-
-        return false;
-    }
 }