Remove the outgoing_quotes feature flag, making the feature unconditional (#36130)

app/javascript/mastodon/utils/environment.ts

@@ -12,11 +12,7 @@ export function isProduction() {
   else return import.meta.env.PROD;
 }
 
-export type Features =
-  | 'modern_emojis'
-  | 'outgoing_quotes'
-  | 'fasp'
-  | 'http_message_signatures';
+export type Features = 'modern_emojis' | 'fasp' | 'http_message_signatures';
 
 export function isFeatureEnabled(feature: Features) {
   return initialState?.features.includes(feature) ?? false;