Adding 3.10 to the UT CI pipeline

Author: vrdmr

.github/workflows/ut_ci_workflow.yml

@@ -20,7 +20,7 @@ jobs:
     strategy:
       fail-fast: true
       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/checkout@v2
     - name: Set up Python ${{ matrix.python-version }}