Remove repeated activation call to prevent confusing log message

The previous logic triggered the activation twice, even when no issue
occured. This lead to this message in the log:

```
rest-session:openapi_session.py:126 < [422] {"title": "The operation has
failed.", "status": 422, "detail": "Currently there are no changes to
activate."}
```

Change-Id: I273f7044ff6c7086909a7140845d676c25cc9fb7

tests/composition/controller_site_interactions/test_rename_preserves_registration.py

@@ -3,7 +3,6 @@
 # This file is part of Checkmk (https://checkmk.com). It is subject to the terms and
 # conditions defined in the file COPYING, which is part of this source code package.
 
-import time
 from contextlib import suppress
 from pathlib import Path
 
@@ -15,23 +14,6 @@
 from cmk.utils.hostaddress import HostName
 
 
-def _activate_changes_and_wait_for_completion_with_retries(site: Site) -> None:
-    """The CMC might be started, but not quite ready. Retry a couple of times.
-
-    Since we added valgrind in c024fd3ebcc the initialization of the core takes longer.
-    Livestatus might not be available for an "activate changes" shortly after a core restart (as during host renaming).
-    """
-    for _atempt in range(10):
-        try:
-            site.openapi.activate_changes_and_wait_for_completion()
-            return
-        except UnexpectedResponse:  # kind of 'expected' after all
-            time.sleep(1)
-
-    # try once more to reveal the exception
-    site.openapi.activate_changes_and_wait_for_completion()
-
-
 def _test_rename_preserves_registration(
     *,
     central_site: Site,
@@ -59,7 +41,7 @@ def _test_rename_preserves_registration(
             hostname_new=new_hostname,
             etag=response_create.headers["ETag"],
         )
-        _activate_changes_and_wait_for_completion_with_retries(central_site)
+        central_site.openapi.activate_changes_and_wait_for_completion()
         controller_status = controller_status_json(agent_ctl)
         try:
             assert (