ci: fix PR not triggering workflows by switching back to pytestbot access token

The builtin actions token is not allowed to trigger further workflows.
So when we create a PR using that token, the PR checks don't run, and a
maintainer must close & open the PR to make them run. This is quite
annoying, so switch back to the "machine user" approach.

Fixes #9554.

.github/workflows/update-plugin-list.yml

@@ -38,7 +38,7 @@ jobs:
         run: python scripts/update-plugin-list.py
 
       - name: Create Pull Request
-        uses: peter-evans/create-pull-request@2455e1596942c2902952003bbb574afbbe2ab2e6
+        uses: peter-evans/create-pull-request@671dc9c9e0c2d73f07fa45a3eb0220e1622f0c5f
         with:
           commit-message: '[automated] Update plugin list'
           author: 'pytest bot <pytestbot@users.noreply.github.com>'
@@ -47,3 +47,4 @@ jobs:
           branch-suffix: short-commit-hash
           title: '[automated] Update plugin list'
           body: '[automated] Update plugin list'
+          token: ${{ secrets.CHATOPS }}