Fix cancel follow request button sometimes saying “Follow back” (#31934)

app/javascript/mastodon/components/follow_button.tsx

@@ -75,10 +75,10 @@ export const FollowButton: React.FC<{
     label = <LoadingIndicator />;
   } else if (relationship.following && relationship.followed_by) {
     label = intl.formatMessage(messages.mutual);
-  } else if (!relationship.following && relationship.followed_by) {
-    label = intl.formatMessage(messages.followBack);
   } else if (relationship.following || relationship.requested) {
     label = intl.formatMessage(messages.unfollow);
+  } else if (relationship.followed_by) {
+    label = intl.formatMessage(messages.followBack);
   } else {
     label = intl.formatMessage(messages.follow);
   }

app/javascript/mastodon/features/account/components/header.jsx

@@ -92,10 +92,10 @@ const messageForFollowButton = relationship => {
 
   if (relationship.get('following') && relationship.get('followed_by')) {
     return messages.mutual;
-  } else if (!relationship.get('following') && relationship.get('followed_by')) {
-    return messages.followBack;
   } else if (relationship.get('following') || relationship.get('requested')) {
     return messages.unfollow;
+  } else if (relationship.get('followed_by')) {
+    return messages.followBack;
   } else {
     return messages.follow;
   }