README.admin: change URL setting.

README.admin

@@ -1,5 +1,8 @@
 # Login as temporary admin user
 #
+
+HOSTNAME="$(hostname -f)"
+
 LOGIN_NAME=admin
 LOGIN_PASS='0x-O-/s7eku9Y./l'
 
@@ -32,7 +35,7 @@ cat <<EOF > /usr/local/src/keycloak/login-credentials-${NEW_ADMIN}.txt
 
    Login into new Keycloak Service:
 
-      URL:        https://keycloak-nd.oopen.de
+      URL:        https://${HOSTNAME}
       USER:       ${NEW_ADMIN}
       PASSSWORD:  ${NEW_ADMIN_PASS}