Prepping new build system

Author: jondecker76

.github/workflows/python-publish.yml

@@ -31,7 +31,7 @@ jobs:
       - name: Install dependencies
         run: |
           python -m pip install --upgrade pip
-          pip install setuptools wheel twine
+          pip install setuptools wheel twine PySimpleGUI update_checker
       - name: Build and publish
         env:
           TWINE_USERNAME: ${{ secrets.PYPI_USERNAME }}