Remove pico-extras from package

Author: earlephilhower

.github/workflows/tag-to-draft-release.yml

@@ -29,7 +29,6 @@ jobs:
         CI_GITHUB_API_KEY: ${{ secrets.GITHUB_TOKEN }}
       run: |
            (cd pico-sdk && git submodule update --init)
-           (cd pico-extras && git submodule update --init)
            (cd ./package && bash ./build_boards_manager_package.sh)
            pip3 install PyGithub
            # Create a draft release and upload the ZIP and JSON files.