feat: move extensions from prefs menu's left pane to General->Advanced section (#718)

app/assets/javascripts/preferences/PreferencesMenu.ts

@@ -11,7 +11,6 @@ const PREFERENCE_IDS = [
   'account',
   'appearance',
   'security',
-  'extensions',
   'listed',
   'shortcuts',
   'accessibility',
@@ -38,7 +37,6 @@ const PREFERENCES_MENU_ITEMS: PreferencesMenuItem[] = [
   { id: 'general', label: 'General', icon: 'settings' },
   // { id: 'appearance', label: 'Appearance', icon: 'themes' },
   { id: 'security', label: 'Security', icon: 'security' },
-  { id: 'extensions', label: 'Extensions', icon: 'tune' },
   { id: 'listed', label: 'Listed', icon: 'listed' },
   // { id: 'shortcuts', label: 'Shortcuts', icon: 'keyboard' },
   // { id: 'accessibility', label: 'Accessibility', icon: 'accessibility' },