fix: dont use turn user/pass

homeserver.yaml.tmpl

@@ -1136,8 +1136,8 @@ turn_shared_secret: "{{ secret "turn_shared_secret" }}"
 # The Username and password if the TURN server needs them and
 # does not use a token
 #
-turn_username: "{{ env "TURN_USERNAME" }}"
-turn_password: "{{ secret "turn_password" }}"
+#turn_username: "TURNSERVER_USERNAME"
+#turn_password: "TURNSERVER_PASSWORD"
 
 # How long generated TURN credentials last
 #