update test target

Author: nov

.github/workflows/spec.yml

@@ -14,10 +14,7 @@ jobs:
     strategy:
       matrix:
         os: ['ubuntu-20.04', 'ubuntu-22.04']
-        ruby-version: ['3.1', '3.2', '3.3']
-        include:
-        - os: 'ubuntu-20.04'
-          ruby-version: '3.0'
+        ruby-version: ['3.2', '3.3', '3.4']
     runs-on: ${{ matrix.os }}
 
     steps: