fixed storage class var name

roles/matrix-synapse/defaults/main.yml

@@ -604,7 +604,7 @@ matrix_synapse_media_storage_provider_s3_config_yaml: |
   "endpoint_url": {{ matrix_synapse_media_storage_provider_s3_endpoint_url|to_json }},
   "access_key_id": {{ matrix_synapse_media_storage_provider_s3_access_key_id|to_json }},
   "secret_access_key": {{ matrix_synapse_media_storage_provider_s3_secret_access_key|to_json }},
-  "storage_class": {{ matrix_synapse_s3_media_store_storage_class|to_json }},
+  "storage_class": {{ matrix_synapse_media_storage_provider_s3_storage_class|to_json }},
   "threadpool_size": {{ matrix_synapse_media_storage_provider_s3_threadpool_size }}
 
 # Goofys S3 Integration