Update test.yml

removing the python 3.6 and ubuntu special cases

Author: karen-avetisyan-mc

.github/workflows/test.yml

@@ -19,10 +19,6 @@ jobs:
           - 3.9
         include:
           - os: "ubuntu-latest"
-          # There is no build for Python 3.9 in ubuntu>20.04.
-          # This unclude can be removed when we drop support for Python 3.9.
-          - os: "ubuntu-20.04"
-            python-version: "3.9"
     steps:
       - uses: actions/checkout@v2
         with: