Update Documentation: Federated Calendar Shares

Clarified that existing federated calendar shares will be deleted when the feature is disabled.

Signed-off-by: Vedant-Arora <139130598+Vedant-Arora@users.noreply.github.com>

Author: Vedant-Arora

admin_manual/groupware/calendar.rst

@@ -149,7 +149,7 @@ Run the following command to disable creating new federated calendar shares for
 
   sudo -E -u www-data php occ config:app:set dav enableCalendarFederation --type=bool --value=false
 
-Note that existing shares will not be deleted when the feature is disabled.
+Note that existing shares will be deleted when the feature is disabled as they will fail to sync.
 
 Trash bin
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