Use a DummyFrozenJob in build cleanup

There is a place where we try to clean up builds that we may no
longer have FrozenJobs for; but the cleanup methods expect FrozenJob
objects essentially just to get the job name.

To make it more clear that's what's happening, use a dedicated object
to pass that information.

Change-Id: Ieb85bcba6d9a184e28120953adf882e4720621b2

zuul/scheduler.py

@@ -2,7 +2,7 @@
 # Copyright 2013 OpenStack Foundation
 # Copyright 2013 Antoine "hashar" Musso
 # Copyright 2013 Wikimedia Foundation Inc.
-# Copyright 2021-2022 Acme Gating, LLC
+# Copyright 2021-2024 Acme Gating, LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License"); you may
 # not use this file except in compliance with the License. You may obtain
@@ -66,7 +66,6 @@ from zuul.model import (
     EnqueueEvent,
     FilesChangesCompletedEvent,
     HoldRequest,
-    Job,
     MergeCompletedEvent,
     NodesProvisionedEvent,
     PromoteEvent,
@@ -172,6 +171,12 @@ class SchedulerStatsElection(SessionAwareElection):
         super().__init__(client.client, self.election_root)
 
 
+class DummyFrozenJob:
+    """Some internal methods expect a FrozenJob for cleanup;
+    use this when we don't actually have one"""
+    pass
+
+
 class Scheduler(threading.Thread):
     """The engine of Zuul.
 
@@ -2878,8 +2883,10 @@ class Scheduler(threading.Thread):
             # allows reporting the build via SQL and cleaning up build
             # resources.
             build = Build()
-            job = Job(event.job_name)
+            job = DummyFrozenJob()
+            job.name = event.job_name
             job.uuid = event.job_uuid
+            job.provides = []
             # MODEL_API < 25
             job._job_id = job.uuid or job.name
             build._set(