Try to work around /actions/runner-images/issues/1202

.github/workflows/python-build-executables.yml

@@ -18,7 +18,7 @@ jobs:
     - name: Install dependencies
       run: |
         pip install --upgrade --force-reinstall pip setuptools requirements-parser
-        pip install --upgrade --force-reinstall -r requirements.txt
+        pip install --upgrade --force-reinstall --no-cache-dir -r requirements.txt
         pip install --upgrade --force-reinstall torch==1.5.1+cpu torchvision==0.6.1+cpu -f https://download.pytorch.org/whl/torch_stable.html
     - name: Build UI files and other resources
       run: |