ansible-middleware#226: add proper default value for proxy-headers

roles/keycloak_quarkus/defaults/main.yml

@@ -91,7 +91,10 @@ keycloak_quarkus_hostname_strict: true
 # If all applications use the public URL this option should be enabled.
 keycloak_quarkus_hostname_strict_backchannel: false
 
-# proxy address forwarding mode if the server is behind a reverse proxy. [none, edge, reencrypt, passthrough]
+# The proxy headers that should be accepted by the server. ['', 'forwarded', 'xforwarded']
+keycloak_quarkus_proxy_headers: ""
+
+# deprecated: proxy address forwarding mode if the server is behind a reverse proxy. [none, edge, reencrypt, passthrough]
 keycloak_quarkus_proxy_mode: edge
 
 # disable xa transactions