Support actions and reusable workflows from private repos (#32562)

Resolve https://gitea.com/gitea/act_runner/issues/102

This PR allows administrators of a private repository to specify some
collaborative owners. The repositories of collaborative owners will be
allowed to access this repository's actions and workflows.

Settings for private repos:


![image](https://github.com/user-attachments/assets/e591c877-f94d-48fb-82f3-3b051f21557e)

---

This PR also moves "Enable Actions" setting to `Actions > General` page

<img width="960" alt="image"
src="https://github.com/user-attachments/assets/49337ec2-afb1-4a67-8516-5c9ef0ce05d4"
/>

<img width="960" alt="image"
src="https://github.com/user-attachments/assets/f58ee6d5-17f9-4180-8760-a78e859f1c37"
/>

---------

Signed-off-by: Zettat123 <zettat123@gmail.com>
Co-authored-by: ChristopherHX <christopher.homberger@web.de>

models/fixtures/action_run.yml

@@ -139,3 +139,23 @@
   updated: 1683636626
   need_approval: 0
   approved_by: 0
+-
+  id: 804
+  title: "use a private action"
+  repo_id: 60
+  owner_id: 40
+  workflow_id: "run.yaml"
+  index: 189
+  trigger_user_id: 40
+  ref: "refs/heads/master"
+  commit_sha: "6e64b26de7ba966d01d90ecfaf5c7f14ef203e86"
+  event: "push"
+  trigger_event: "push"
+  is_fork_pull_request: 0
+  status: 1
+  started: 1683636528
+  stopped: 1683636626
+  created: 1683636108
+  updated: 1683636626
+  need_approval: 0
+  approved_by: 0