Update gcloud versions (#374)

Update latest gcloud versions

Author: google-github-actions-bot

data/versions.json

@@ -512,5 +512,6 @@
   "553.0.0",
   "554.0.0",
   "555.0.0",
-  "556.0.0"
+  "556.0.0",
+  "557.0.0"
 ]