fix(pnpm-install): pass working-directory to package_json_file

pnpm/action-setup reads the pnpm version from package.json. When
the project lives in a subdirectory (e.g. impit-node), the root
has no package.json and the version lookup fails. Forward the
working-directory input so it finds the right file.

Author: B4nan

pnpm-install/action.yaml

@@ -20,6 +20,7 @@ runs:
       name: Install pnpm
       with:
         run_install: false
+        package_json_file: ${{ inputs.working-directory }}/package.json
 
     - name: Expose pnpm config(s) through "$GITHUB_OUTPUT"
       id: pnpm-config