Fix typos.

wiki/src/contribute/working_together/roles/sysadmins.mdwn

@@ -236,15 +236,15 @@ Below, importance level is evaluated based on:
   - [[How to add checks to our monitoring setup|roles/sysadmins/adding_icinga2_checks]]
 * importance: critical (needed to ensure that other, critical services are working)
 
-## Internal xmpp service
+## Internal XMPP service
 
-* purpose: an internal xmpp service that can be used by Tails developers and some contributors.
+* purpose: an internal XMPP service that can be used by Tails developers and some contributors.
 * access: at the moment everyone that is on the tails-summit mailinglist has and/or can
   request an account.
 * tools: prosody
-* configuration: 
+* configuration:
   - `tails::prosody` in [[!tails_gitweb_repo puppet-tails]]
-* importance: low 
+* importance: low
 
 ## Jenkins