Pin Ruby version to 3.4.4 in CI workflows

ruby-version: ruby was resolving to Ruby 4.0.5 instead of reading
.ruby-version, causing frozen bundler to reject the mismatched lockfile.

Author: jeremiahlukus

.github/workflows/release.yml

@@ -19,6 +19,6 @@ jobs:
         uses: ruby/setup-ruby@v1
         with:
           bundler-cache: true
-          ruby-version: ruby
+          ruby-version: "3.4.4"
 
       - uses: rubygems/release-gem@v1

.github/workflows/test.yml

@@ -10,6 +10,6 @@ jobs:
         uses: ruby/setup-ruby@v1
         with:
           bundler-cache: true
-          ruby-version: ruby
+          ruby-version: "3.4.4"
       - name: Test
         run: bundle exec rake test