Update docs/hooks/hook_civicrm_alterExternUrl.md

docs/hooks/hook_civicrm_alterExternUrl.md

@@ -49,7 +49,7 @@ function MODULENAME_civicrm_alterExternUrl(&$url, $path, $query, $fragment, $abs
 !!!note "Notes"
 
 * The function examines `$path`, `$query`, `$fragment`, `$absolute` -- these are the main *inputs*.
-* The function outputs the `$url` (per [PSR-7 UriInterface](https://www.php-fig.org/psr/psr-7/#35-psrhttpmessageuriinterface)).
+    * The function outputs the `$url` (per [PSR-7 UriInterface](https://www.php-fig.org/psr/psr-7/#35-psrhttpmessageuriinterface)).
 * The outputted `$url` *incorporates* the requested values, but they do not have to be used *literally*.
   In this case, the requested `$path` (`extern/open`) is very different from the concrete path (`/open/tracker/wrapper`).