fix: missing plex.tv url in images remotePatterns (#1356)

This fixes a 400 error while fetching user's avatar from plex api during user import.

next.config.js

@@ -11,6 +11,7 @@ module.exports = {
       { hostname: 'gravatar.com' },
       { hostname: 'image.tmdb.org' },
       { hostname: 'artworks.thetvdb.com' },
+      { hostname: 'plex.tv' },
     ],
   },
   webpack(config) {