Update roles for export

Author: EXPEkesheth

articles/healthcare-apis/fhir/configure-export-data.md

@@ -14,7 +14,9 @@ ms.author: kesheth
 
 The FHIR service supports the `$export` operation [specified by HL7](https://hl7.org/fhir/uv/bulkdata/export/index.html) for exporting FHIR data from a FHIR server. In the FHIR service implementation, calling the `$export` endpoint causes the FHIR service to export data into a pre-configured Azure storage account.
 
-There are three steps in setting up the `$export` operation for the FHIR service:
+Ensure you are granted with application roles - 'FHIR Data Contributor role' and 'FHIR Data exporter role' prior to configuring export. To understand more on application roles, see [Authentication and Authorization for FHIR service](healthcare-apis/authentication-authorization#application-roles).
+
+Below are three steps in setting up the `$export` operation for the FHIR service-
 
 - Enable a managed identity for the FHIR service.
 - Configure a new or existing Azure Data Lake Storage Gen2 (ADLS Gen2) account and give permission for the FHIR service to access the account.