GH_Actions: install dev deps for building a release

Author: nassauwinter

.github/workflows/build_and_load_to_pypi.yaml

@@ -29,7 +29,7 @@ jobs:
       - name: Install python dependencies
         run: |
           cd ${{ github.workspace }}/zephyr_source/
-          pipenv install
+          pipenv install --dev
 
       - name: Build distribution archives
         run: python3 -m build