Fix permissions of output folder (#4)

action.yml

@@ -57,8 +57,12 @@ runs:
     - name: Setup environment
       shell: bash
       run: |
+        # Ensure node_modules folder will have correct permissions
         mkdir -p ${{github.action_path}}/node_modules
 
+        # Ensure parent directory containing output file exists
+        mkdir -p $(dirname "${{ github.workspace }}/${{ inputs.output }}")
+
         # Ensure docker container can write this workspace as an unprivileged user
         chmod ugoa+rw -R ${{ github.workspace }} ${{github.action_path}}
 
@@ -71,9 +75,6 @@ runs:
         ${{ inputs.customizations }}
         __EOF__
 
-        # Ensure parent directory of output file exists
-        mkdir -p $(dirname "${{ github.workspace }}/${{ inputs.output }}")
-
         # Prepare inputs that should be passed to the docker container.
         cat<<__EOF__>docker.env
         GITHUB_WORKSPACE=${{ github.workspace }}