test(ansible): the swarm prune guard's comment states why, not when (#6399)

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tests/core/test_swarm_prune.py

@@ -35,8 +35,8 @@ def test_the_playbook_is_listed_and_asks_before_it_runs():
     script = next(t for t in play["tasks"] if "ansible.builtin.script" in t)
     assert script["check_mode"] is False and "--dry-run" in script["ansible.builtin.script"]["cmd"]
     # No docker prune touches images: an image swarm pulled by digest has no
-    # tag, and Docker calls that dangling (on 2026-10-25 a `system prune`
-    # took 29 a node was keeping for the other's services).
+    # tag, and Docker calls that dangling, so a `system prune` removes the
+    # images a node keeps for the other node's services.
     commands = yaml.safe_dump([t for t in play["tasks"] if "ansible.builtin.command" in t])
     assert "'system'" not in commands and "'image'" not in commands
     assert "'container', 'prune'" in commands and "'builder', 'prune'" in commands