Make sure libWiiPy is built and installed so Sphinx can import it

.github/workflows/sphinx-docs.yml

@@ -38,7 +38,11 @@ jobs:
         run: |
           python -m pip install --upgrade pip
           pip install -r requirements.txt
-      - name: Build with Sphinx
+      - name: Build and Install libWiiPy for Sphinx
+        run: |
+          python -m build
+          pip install dist/libwiipy*.tar.gz
+      - name: Build Documentation with Sphinx
         run: |
           python -m sphinx -M html docs/source/ docs/build/
       - name: Upload artifact