fix: hide private key from the logs for gce driver

When instance is waited, loop contain all server data, including
metadata, which contains ssh private key.

This key is ephimerial (get removed when Molecule finished), but,
nevertheless, is a private key, which give access to some server,
printed in the plain text.

test/gce/scenarios/linux/tasks/create_linux_instance.yml

@@ -56,3 +56,6 @@
     search_regex: SSH
     delay: 10
   loop: "{{ server.results }}"
+  loop_control:
+    label: "{{ item.name }}"
+