ci: publish gem with compatible Ruby (#11)

Co-authored-by: kriptoburak <kriptoburak@users.noreply.github.com>

Author: Burak Bayır

.github/workflows/publish-gem.yml

@@ -28,7 +28,7 @@ jobs:
         uses: ruby/setup-ruby@c4e5b1316158f92e3d49443a9d58b31d25ac0f8f # v1.306.0
         with:
           bundler-cache: true
-          ruby-version: "3.2"
+          ruby-version: "4.0"
 
       - name: Publish to RubyGems.org
         uses: rubygems/release-gem@052cc82692552de3ef2b81fd670e41d13cba8092 # v1.4.0