Fix missing outputs for jobs with matrix (#32823)

Fix #32795

If a job uses a matrix, multiple `ActionRunJobs` may have the same
`JobID`. We need to merge the outputs of these jobs to make them
available to the jobs that need them.

(cherry picked from commit 7269130d2878d51dcdf11f7081a591f85bd493e8)

Conflicts:
	models/fixtures/action_run.yml
	models/fixtures/action_run_job.yml
  trivial context conflicts

models/fixtures/action_run.yml

@@ -413,6 +413,25 @@
       },
       "total_commits": 0
     }
+-
+  id: 793
+  title: "job output"
+  repo_id: 4
+  owner_id: 1
+  workflow_id: "test.yaml"
+  index: 189
+  trigger_user_id: 1
+  ref: "refs/heads/master"
+  commit_sha: "c2d72f548424103f01ee1dc02889c1e2bff816b0"
+  event: "push"
+  is_fork_pull_request: 0
+  status: 1
+  started: 1683636528
+  stopped: 1683636626
+  created: 1683636108
+  updated: 1683636626
+  need_approval: 0
+  approved_by: 0
 -
   id: 891
   title: "update actions"