Fix unfollow confirmations in account directory (#12922)

Fixes #12921

app/javascript/mastodon/features/directory/components/account_card.js

@@ -22,6 +22,7 @@ const messages = defineMessages({
   requested: { id: 'account.requested', defaultMessage: 'Awaiting approval' },
   unblock: { id: 'account.unblock', defaultMessage: 'Unblock @{name}' },
   unmute: { id: 'account.unmute', defaultMessage: 'Unmute @{name}' },
+  unfollowConfirm: { id: 'confirmations.unfollow.confirm', defaultMessage: 'Unfollow' },
 });
 
 const makeMapStateToProps = () => {