fix pnpm setup step (#465)

Author: Christian Theilemann

.github/workflows/copy-processor-images-to-dockerhub.yaml

@@ -57,7 +57,7 @@ jobs:
         with:
           node-version-file: .node-version
 
-      - uses: pnpm/action-setup@d882d12c64e032187b2edb46d3a0d003b7a43598 # pin https://github.com/pnpm/action-setup/releases/tag/v2.4.0
+      - uses: pnpm/action-setup@fe02b34f77f8bc703788d5817da081398fad5dd2 # pin https://github.com/pnpm/action-setup/releases/tag/v4.0.0
         with:
           run_install: false
           package_json_file: scripts/package.json