actually use the configured turn servers...

rootfs/etc/confd/templates/server.yaml.tmpl

@@ -1038,11 +1038,11 @@ url_preview_accept_language:
 
 # The public URIs of the TURN server to give to clients
 #
-#turn_uris: [{{getenv "TURN_URIS" ""}}]
+turn_uris: [{{getenv "TURN_URIS" ""}}]
 
 # The shared secret used to compute passwords for the TURN server
 #
-#turn_shared_secret: "{{getenv "TURN_SHARED_SECRET"}}"
+turn_shared_secret: "{{getenv "TURN_SHARED_SECRET"}}"
 
 # The Username and password if the TURN server needs them and
 # does not use a token
@@ -2589,4 +2589,3 @@ redis:
   # Optional password if configured on the Redis instance
   #
   #password: <secret_password>
-