exclude py3.6 from test matrix for ubuntu

Author: fgregg

.github/workflows/tests.yml

@@ -13,11 +13,13 @@ jobs:
 
     strategy:
       matrix:
-        python-version: ["2.7", "3.6", "3.7", "3.8", "3.9", "3.10"]
+        python-version: ["2.7", "3.6", "3.7", "3.8", "3.9", "3.10", "3.11"]
         os: [ubuntu-latest, macos-latest, windows-latest]
         exclude:
           - os: windows-latest
             python-version: "2.7"
+          - os: ubuntu-latest
+            python-version: "3.6"
       fail-fast: false
 
     steps:
@@ -39,4 +41,4 @@ jobs:
         run: "./update_cpp.sh"
 
       - name: "Run tox targets for ${{ matrix.python-version }}"
-        run: "python -m tox"
+        run: "python -m tox"