Update GitHub Actions workflows. (#575)

This PR was automatically generated by the
update-workflows-single-bridged-provider workflow in the pulumi/ci-mgmt
repo, from commit 4ac37ece8be37ce71d07d3e42b89c7c306173b9b.

.github/workflows/export-repo-secrets.yml

@@ -0,0 +1,25 @@
+permissions: write-all # Equivalent to default permissions plus id-token: write
+name: Export secrets to ESC
+on: [workflow_dispatch]
+jobs:
+  export-to-esc:
+    runs-on: ubuntu-latest
+    name: export GitHub secrets to ESC
+    steps:
+      - name: Generate a GitHub token
+        id: generate-token
+        uses: actions/create-github-app-token@v1
+        with:
+          app-id: 1256780 # Export Secrets GitHub App
+          private-key: ${{ secrets.EXPORT_SECRETS_PRIVATE_KEY }}
+      - name: Export secrets to ESC
+        uses: pulumi/esc-export-secrets-action@v1
+        with:
+          organization: pulumi
+          org-environment: github-secrets/${{ github.repository_owner }}-${{ github.event.repository.name }}
+          exclude-secrets: EXPORT_SECRETS_PRIVATE_KEY
+          github-token: ${{ steps.generate-token.outputs.token }}
+          oidc-auth: true
+          oidc-requested-token-type: urn:pulumi:token-type:access_token:organization
+        env:
+          GITHUB_SECRETS: ${{ toJSON(secrets) }}