Merge pull request sshuttle#694 from cclauss/patch-1

pythonpackage.yml: Add Python 3.10 to the testing

Author: brianmay

.github/workflows/pythonpackage.yml

@@ -17,7 +17,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: [3.6, 3.7, 3.8, 3.9]
+        python-version: [3.6, 3.7, 3.8, 3.9, "3.10"]
 
     steps:
     - uses: actions/[email protected]