Update GitHub Actions workflows. (#716)

This PR was automatically generated by the
update-workflows-ecosystem-providers workflow in the pulumi/ci-mgmt
repo, from commit 02f02bb0bfe879d167ed8f335b4950208454bafb.

---------

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

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

@@ -8,7 +8,7 @@ jobs:
     steps:
       - name: Generate a GitHub token
         id: generate-token
-        uses: actions/create-github-app-token@v1
+        uses: actions/create-github-app-token@29824e69f54612133e76f7eaac726eef6c875baf # v2
         with:
           app-id: 1256780 # Export Secrets GitHub App
           private-key: ${{ secrets.EXPORT_SECRETS_PRIVATE_KEY }}