🧪⇪ Bump galaxy_ng to v4.9.0 in tests

It updates the underlying `pulp_ansible` to v0.20.2, which fixes a
race condition that is occasiontally observable in our CI when
provisioning the initial dummy collections for testing.

Refs:

  * https://github.com/ansible/galaxy_ng/releases/tag/4.9.0
  * ansible/galaxy_ng#1950
  * ansible/galaxy#3267
  * pulp/pulp_ansible#1571
  * pulp/pulp_ansible#1572
  * pulp/pulp_ansible#1595
  * pulp/pulp_ansible#1623
  * pulp/pulp_ansible#1624

test/lib/ansible_test/_internal/commands/integration/cloud/galaxy.py

@@ -98,7 +98,7 @@ def __init__(self, args: IntegrationConfig) -> None:
 
         self.image = os.environ.get(
             'ANSIBLE_PULP_CONTAINER',
-            'quay.io/pulp/galaxy:4.7.1'
+            'quay.io/pulp/galaxy:4.9.0'  # https://github.com/ansible/galaxy_ng
         )
 
         self.uses_docker = True