chore(deps): update ruby docker tag to v4

Author: renovate[bot]

.github/workflows/config.yml

@@ -5,7 +5,7 @@ jobs:
     name: Prekin CI
     runs-on: ubuntu-latest
     container:
-      image: ruby:3.4.9
+      image: ruby:4.0.1
       env:
         BUNDLE_PATH: vendor/bundle
     steps: