Targeted link in index page to azure api for fhir index yml file

Author: SteveWohl

articles/index.yml

@@ -644,7 +644,7 @@ productDirectory:
       azureCategories:
         - databases
         - integration
-      url: healthcare-apis/azure-api-for-fhir
+      url: healthcare-apis/azure-api-for-fhir/index.yml
     # Card
     - title: Azure Cache for Redis
       summary: Power applications with high-throughput, low-latency data access