fix: Update docs/source/UserGuide/GettingStarted/GettingUserIdentity/index.rst

Co-authored-by: fstagni <[email protected]>

Author: TaykYoku

docs/source/UserGuide/GettingStarted/GettingUserIdentity/index.rst

@@ -63,7 +63,7 @@ Starting with the 8.0 version of DIRAC, it is possible to authorize users throug
 such as EGI Checkin [https://www.egi.eu/services/check-in/] or WLCG IAM (https://indigo-iam.github.io/v/current/).
 You do not need a certificate for this in a terminal, the main thing is that you must be registered in one of the supported IdP. The registration process is different for each IdP.
 
-Once your account is created, you will be able to register with DIRAC Authorization Server using *--use-diracas* key for the `dirac-login` command::
+Once your account is created, you will be able to register with DIRAC Authorization Server using *--use-diracas* switch of the `dirac-login` command::
 
   dirac-login <user_group> --use-diracas