Remove Python 3.6 from build matrix

.github/workflows/ci.yml

@@ -45,7 +45,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        pyver: ["3.6.15", "3.7.15", "3.8.16", "3.9.16", "3.10.10"]
+        pyver: ["3.7", "3.8", "3.9", "3.10", "3.11"]
       fail-fast: true
     steps:
       - name: Install deps