CI: promote the Ruby 3.2 build step to non-experimental

Author: orien

.github/workflows/test.yml

@@ -9,11 +9,9 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ruby_version: ["2.3", "2.4", "2.5", "2.6", "2.7", "3.0", "3.1"]
+        ruby_version: ["2.3", "2.4", "2.5", "2.6", "2.7", "3.0", "3.1", "3.2"]
         experimental: [false]
         include:
-          - ruby_version: "3.2"
-            experimental: true
           - ruby_version: "ruby-head"
             experimental: true