fix workflow

Author: wing328

.github/workflows/samples-r-petstore.yaml

@@ -7,7 +7,6 @@ on:
   pull_request:
     paths:
       - 'samples/client/petstore/R/**'
-  pull_request:
 
 jobs:
   build:
@@ -18,6 +17,14 @@ jobs:
       matrix:
         sample:
           - 'samples/client/petstore/R/'
+    services:
+      petstore-api:
+        image: swaggerapi/petstore
+        ports:
+          - 80:8080
+        env:
+          SWAGGER_HOST: http://petstore.swagger.io
+          SWAGGER_BASE_PATH: /v2
     steps:
       - uses: actions/checkout@v4
       - uses: r-lib/actions/setup-r@v2