Build binaries with Python 3.9

Author: n2iw

.github/workflows/distribute-binary-files.yaml

@@ -17,7 +17,7 @@ jobs:
       - name: Set up Python
         uses: actions/setup-python@v2
         with:
-          python-version: '3.x'
+          python-version: '3.9'
 
       - name: Install dependencies
         run: |
@@ -73,7 +73,7 @@ jobs:
       - name: Set up Python
         uses: actions/setup-python@v2
         with:
-          python-version: '3.x'
+          python-version: '3.9'
 
       - name: Install dependencies
         run: |
@@ -116,7 +116,7 @@ jobs:
       - name: Set up Python
         uses: actions/setup-python@v2
         with:
-          python-version: '3.x'
+          python-version: '3.9'
 
       - name: Install dependencies
         run: |