.github: move repo lockdown to the v2 configuration

I was getting prompted by GitHub for new permissions but it turns out
per https://github.com/dessant/repo-lockdown/issues/6

:

  Repo Lockdown has been rewritten for GitHub Actions, offering new
  features and better control over your automation presets. The legacy
  GitHub App has been deprecated, and the public instance of the app
  has been shut down.

So this is what I've done. As the issues tab is disabled I've removed
the handling for issues from the new version.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Willian Rampazzo <willianr@redhat.com>
Message-Id: <20211004154308.2114870-1-alex.bennee@linaro.org>

.github/lockdown.yml

-# Configuration for Repo Lockdown - https://github.com/dessant/repo-lockdown
-
-# Close issues and pull requests
-close: true
-
-# Lock issues and pull requests
-lock: true
-
-issues:
-  comment: |
-    Thank you for your interest in the QEMU project.
-
-    This repository is a read-only mirror of the project's repostories hosted
-    at https://gitlab.com/qemu-project/qemu.git.
-    The project does not process issues filed on GitHub.
-
-    The project issues are tracked on GitLab:
-    https://gitlab.com/qemu-project/qemu/-/issues
-
-    QEMU welcomes bug report contributions. You can file new ones on:
-    https://gitlab.com/qemu-project/qemu/-/issues/new
-
-pulls:
-  comment: |
-    Thank you for your interest in the QEMU project.
-
-    This repository is a read-only mirror of the project's repostories hosted
-    on https://gitlab.com/qemu-project/qemu.git.
-    The project does not process merge requests filed on GitHub.
-
-    QEMU welcomes contributions of code (either fixing bugs or adding new
-    functionality). However, we get a lot of patches, and so we have some
-    guidelines about contributing on the project website:
-    https://www.qemu.org/contribute/

.github/workflows/lockdown.yml

+# Configuration for Repo Lockdown - https://github.com/dessant/repo-lockdown
+
+name: 'Repo Lockdown'
+
+on:
+  pull_request_target:
+    types: opened
+
+permissions:
+  pull-requests: write
+
+jobs:
+  action:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: dessant/repo-lockdown@v2
+        with:
+          pull-comment: |
+            Thank you for your interest in the QEMU project.
+
+            This repository is a read-only mirror of the project's repostories hosted
+            on https://gitlab.com/qemu-project/qemu.git.
+            The project does not process merge requests filed on GitHub.
+
+            QEMU welcomes contributions of code (either fixing bugs or adding new
+            functionality). However, we get a lot of patches, and so we have some
+            guidelines about contributing on the project website:
+            https://www.qemu.org/contribute/
+          lock-pull: true
+          close-pull: true