Expand list of tested rubies

Author: BiggerNoise

.github/workflows/tests.yml

@@ -8,20 +8,20 @@ on:
 
 jobs:
   test:
-    name: Ruby ${{ matrix.ruby-version }} - ${{ matrix.os }} - ${{ github.event_name }}
+    name: Ruby ${{ matrix.ruby }} - ${{ matrix.os }} - ${{ github.event_name }}
     runs-on: ${{ matrix.os }}
     strategy:
       fail-fast: false
       matrix:
         os:
           - ubuntu-latest
-        ruby-version: [2.6, 2.7, 3.0.0-preview1]
+        ruby: [2.6, 2.7, '3.0', 3.1]
 
     steps:
       - uses: actions/checkout@v2
 
       - name: Set up Ruby
-        uses: ruby/setup-ruby@a699edbce608a2c128dedad88e3b6a0e28687b3c
+        uses: ruby/setup-ruby@v1
         with:
           ruby-version: ${{ matrix.ruby-version }}
           bundler-cache: true