add petstore, update host table

Author: wing328

.github/workflows/samples-ruby.yaml

@@ -26,8 +26,19 @@ jobs:
           - samples/client/petstore/ruby-faraday/
           - samples/client/petstore/ruby-httpx/
           - samples/client/petstore/ruby-autoload/
+    services:
+      petstore-api:
+        image: swaggerapi/petstore
+        ports:
+          - 80:8080
+        env:
+          SWAGGER_HOST: http://petstore.swagger.io
+          SWAGGER_BASE_PATH: /v2
     steps:
       - uses: actions/checkout@v5
+      - name: Add hosts to /etc/hosts
+        run: |
+            sudo echo "127.0.0.1 petstore.swagger.io" | sudo tee -a /etc/hosts
       - uses: ruby/setup-ruby@v1
         with:
           ruby-version: '3.2' # Not needed with a .ruby-version, .tool-versions or mise.toml