Update GitHub Actions workflows. (#851)

This PR was triggered by @t0yv0 generated by the
update-workflows-ecosystem-providers workflow in the pulumi/ci-mgmt
repo, from commit
[daf8aba035d6ed8919db6089c780f56cb7fefc69](daf8aba035).

Co-authored-by: Pulumi Bot <bot@pulumi.com>

.github/workflows/gh-aw-pr-rereview.md

@@ -0,0 +1,20 @@
+---
+on:
+  slash_command:
+    events:
+    - pull_request_comment
+    - pull_request_review_comment
+    name: review-again
+permissions:
+  contents: read
+  id-token: write
+  pull-requests: read
+imports:
+- shared/review.md
+- shared/plugins/code-review/code-review.md
+description: Run PR re-review on explicit maintainer slash command.
+source: pulumi-labs/gh-aw-internal/.github/workflows/gh-aw-pr-rereview.md@8a92f53fac170563f7727cacab2dbedb5d5b9e29
+strict: true
+timeout-minutes: 15
+---
+# Internal PR Re-Review (Slash Command)