gci: Checkout entire history in PyPI build to ensure tags are there

setuptools_scm requires the ability to look up the latest tag.

.github/workflows/pypi.yml

@@ -25,19 +25,26 @@ jobs:
             WORKDIR: contrib/pyln-spec/bolt7/
     steps:
     - uses: actions/checkout@master
+      with:
+        # Need to fetch entire history in order to locate the version tag
+        fetch-depth: 0
+
     - name: Set up Python 3.7
       uses: actions/setup-python@v1
       with:
         python-version: 3.7
+
     - name: Install pypa/build
       run: >-
         python -m pip install build --user
+
     - name: Build a binary wheel and a source tarball
       env:
         WORKDIR: ${{ matrix.WORKDIR }}
       run: >-
         cd ${{ env.WORKDIR}} &&
         python -m build --sdist --wheel --outdir dist/ .
+
     - name: Publish distribution 📦 to Test PyPI
       uses: pypa/gh-action-pypi-publish@master
       env:
@@ -47,6 +54,7 @@ jobs:
         repository_url: https://test.pypi.org/legacy/
         packages_dir: "${{ env.WORKDIR}}/dist"
         skip_existing: true
+
     - name: Publish distribution 📦 to PyPI
       if: startsWith(github.ref, 'refs/tags')
       uses: pypa/gh-action-pypi-publish@master