Clarify Server URL scheme requirements in sync instructions

Updated note about Server URL requirements in Thunderbird sync instructions.

Signed-off-by: Theking2 <[email protected]>

Author: theking2

user_manual/groupware/sync_thunderbird.rst

@@ -36,7 +36,8 @@ Calendars
 #. Type your **Username** and **Location** (Server URL), then click on **Find Calendars**.
 #. Choose which calendars you want to add and click **Subscribe**
 
-> **_NOTE:_**  The Server URL does not required a scheme (`https://`) but might need a path like `/remote.php/dav`
+
+.. note:: The Server URL does not require a scheme (`https://`) but might need a path like `/remote.php/dav`
 
 Same thing here, if you later want to add more calendars, just redo the procedure.