Specify trusted publisher environment (#5)

Author: daneah

.github/workflows/packaging.yml

@@ -115,6 +115,7 @@ jobs:
     needs: [format, lint, typecheck, test, docs]
     if: startsWith(github.ref, 'refs/tags')
     runs-on: ubuntu-latest
+    environment: release
     permissions:
       id-token: write
       contents: write