docs: update highlighting in Multiple variables section

Co-Authored-By: [email protected] <[email protected]>

Author: devin-ai-integration[bot]

fern/products/api-def/openapi-pages/extensions/sdk-variables.mdx

@@ -107,7 +107,7 @@ List<Plant> plants = client.listPlants();
 
 You can define multiple SDK variables for complex path hierarchies:
 
-```yaml {1-8,18,24} title="openapi.yml"
+```yaml {1-7,17,23} title="openapi.yml"
 x-fern-sdk-variables:
   gardenId:
     type: string