refactor: replace OpenAPI Validate Action with Redocly CLI for validation

Author: Valentin Schneider-Lunitz

.github/workflows/ci.yml

@@ -41,10 +41,7 @@ jobs:
     steps:
       - name: Check out head branch
         uses: actions/checkout@v4
-      - name: Run OpenAPI Validate Action
-        uses: swaggerexpert/[email protected]
-        env:
-          PUPPETEER_NO_SANDBOX: "true"
-          PUPPETEER_EXECUTABLE_PATH: "/usr/bin/chromium-browser"
-        with:
-          definition-file: openapi/workflow_execution_service.openapi.yaml
+      - name: Install Redocly CLI
+        run: npm install -g @redocly/cli
+      - name: Validate OpenAPI definition
+        run: redocly lint openapi/workflow_execution_service.openapi.yaml