infra: test release skip attestations (#27853)

Author: baskaryan

.github/workflows/_test_release.yml

@@ -98,3 +98,4 @@ jobs:
           # This is *only for CI use* and is *extremely dangerous* otherwise!
           # https://github.com/pypa/gh-action-pypi-publish#tolerating-release-package-file-duplicates
           skip-existing: true
+          attestations: false