Use /lookup for username availability with Pleroma

Signed-off-by: marcin mikołajczak <git@mkljczk.pl>

app/soapbox/utils/features.js

@@ -70,7 +70,10 @@ export const getFeatures = createSelector([
       v.software === MASTODON && gte(v.compatVersion, '3.0.0'),
       features.includes('profile_directory'),
     ]),
-    accountLookup: v.software === MASTODON && gte(v.version, '3.4.0'),
+    accountLookup: any([
+      v.software === MASTODON && gte(v.compatVersion, '3.4.0'),
+      v.software === PLEROMA && gte(v.version, '2.4.50'),
+    ]),
   };
 });