CI config update, show OS info

.github/workflows/main.yml

@@ -25,6 +25,8 @@ jobs:
         uses: actions/setup-python@v2
         with:
           python-version: ${{ matrix.python-version }}
+      - name: check OS
+        run: cat /etc/os-release
       - name: Install dependencies
         run: |
           sudo apt update