Update validate_config.yml

roles/custom/matrix-element-call/tasks/validate_config.yml

@@ -12,6 +12,6 @@
     - {'name': 'matrix_element_call_image', when: true}
     - {'name': 'matrix_jwt_service_image', when: true}
     - {'name': 'matrix_livekit_image', when: true}
-    - {'name': 'matrix_redis_image', when: true}
+    - {'name': 'redis_image', when: true}
     - {'name': 'matrix_element_call_livekit_dev_key', when: true}
     - {'name': 'matrix_element_call_livekit_service_url', when: true}