Update GitHub Actions workflows. (#503)

This PR was automatically generated by the
update-workflows-ecosystem-providers workflow in the pulumi/ci-mgmt
repo, from commit 4e26123dab993a961fa2e8477574d8ce97f5fed6.

.github/workflows/run-acceptance-tests.yml

@@ -391,6 +391,8 @@ on:
   pull_request:
     branches:
     - master
+    - v*
+    - feature*
     paths-ignore:
     - CHANGELOG.md
   repository_dispatch: