Update documentation to also mention the --config-url option (#3683)

* Add missing config-url option

* Update example in documentation

Author: giftkugel

docs/installing/guided.rst

@@ -36,7 +36,12 @@ There are two configuration files, both are optional.
 ``--config``
 ------------
 
-This parameter takes a local or remote :code:`.json` file as argument and contains the overall configuration and menu answers for the guided installer.
+This parameter takes a local :code:`.json` file as argument and contains the overall configuration and menu answers for the guided installer.
+
+``--config-url``
+------------
+
+This parameter takes a remote :code:`.json` file as argument and contains the overall configuration and menu answers for the guided installer.
 
 .. note::
 
@@ -47,7 +52,11 @@ Example usage
 
 .. code-block:: sh
 
-    archinstall --config https://domain.lan/config.json
+    archinstall --config config.json
+
+.. code-block:: sh
+
+    archinstall --config-url https://domain.lan/config.json
 
 The contents of :code:`https://domain.lan/config.json`: