Update extension repo regex to server changes (#554)

src/screens/settings/ServerSettings.tsx

@@ -150,7 +150,7 @@ export const ServerSettings = () => {
                     placeholder="https://github.com/MY_ACCOUNT/MY_REPO/tree/repo"
                     validateItem={(repo) =>
                         !!repo.match(
-                            /https:\/\/(?:www|raw)?(?:github|githubusercontent)\.com\/([^/]+)\/([^/]+)(?:\/(?:tree|blob)\/(.*))?\/?/g,
+                            /https:\/\/(www\.|raw\.)?(github|githubusercontent)\.com\/([^/]+)\/([^/]+)((\/tree|\/blob)?\/([^/\n]*))?(\/([^/\n]*\.json)?)?/g,
                         )
                     }
                     invalidItemError={t('extension.settings.repositories.custom.error.label.invalid_url')}