👷 Remove python3.6 and add python3.10 in CI

Author: pwwang

.github/workflows/build.yml

@@ -8,7 +8,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: [3.6, 3.7, 3.8, 3.9]
+        python-version: [3.7, 3.8, 3.9, "3.10"]
 
     steps:
       - uses: actions/checkout@v2