Remove 3.1 + edge from CI

Rails 8 need 3.2+ so this will never pass.

Author: gmcgibbon

.github/workflows/ci.yml

@@ -13,6 +13,10 @@ jobs:
           - ruby: '3.3'
             rails: '7.1'
             rubyopt: "--enable-frozen-string-literal"
+        exclude:
+          - ruby: '3.1'
+            rails: 'edge'
+            rubyopt: ''
 
     env:
       RAILS_VERSION: ${{ matrix.rails }}