github: add cityhub firmware to release upload

Author: dlech

.github/workflows/release.yml

@@ -35,6 +35,7 @@ jobs:
         run: |
           make $MAKEOPTS -C micropython/mpy-cross
           make $MAKEOPTS -C bricks/movehub
+          make $MAKEOPTS -C bricks/cityhub
           make $MAKEOPTS -C bricks/cplushub
       - name: Get tag
         run: echo "::set-env name=GITHUB_TAG::${GITHUB_REF#*refs/tags/}"
@@ -58,6 +59,16 @@ jobs:
           asset_path: ./bricks/movehub/build/firmware.zip
           asset_name: pybricks-movehub-${{ env.GITHUB_TAG }}.zip
           asset_content_type: application/zip
+      - name: Upload cityhub firmware
+        id: upload-cityhub
+        uses: actions/upload-release-asset@v1
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          upload_url: ${{ steps.create_release.outputs.upload_url }}
+          asset_path: ./bricks/cityhub/build/firmware.zip
+          asset_name: pybricks-cityhub-${{ env.GITHUB_TAG }}.zip
+          asset_content_type: application/zip
       - name: Upload cplushub firmware
         id: upload-cplushub
         uses: actions/upload-release-asset@v1