Merge pull request github#175 from petergoldstein/feature/add_ruby_3_1_to_ci

Add Ruby 3.1 to CI

Author: zerowidth

.github/workflows/ci.yml

@@ -22,6 +22,7 @@ jobs:
           - "2.6"
           - "2.7"
           - "3.0"
+          - "3.1"
     steps:
       - uses: actions/checkout@v2
       - uses: ruby/setup-ruby@v1