Run tests on Ruby 4.0

Author: janko

.github/workflows/ci.yml

@@ -34,9 +34,13 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ruby: ["ruby-3.0", "ruby-3.1", "ruby-3.2", "ruby-3.3", "ruby-3.4", "jruby-9.4"]
+        ruby: ["ruby-3.0", "ruby-3.1", "ruby-3.2", "ruby-3.3", "ruby-3.4", "ruby-4.0", "jruby-9.4"]
         gemfile: ["activerecord-5.1", "activerecord-5.2", "activerecord-6.0", "activerecord-6.1", "activerecord-7.0", "activerecord-7.1", "activerecord-7.2", "activerecord-8.0", "activerecord-8.1"]
         exclude:
+          - ruby: "ruby-4.0"
+            gemfile: "activerecord-5.2"
+          - ruby: "ruby-4.0"
+            gemfile: "activerecord-5.1"
           - ruby: "ruby-3.4"
             gemfile: "activerecord-5.2"
           - ruby: "ruby-3.4"