Update durable-functions-storage-providers.md

managed identity support no longer in preview

Author: lilyjma

articles/azure-functions/durable/durable-functions-storage-providers.md

@@ -89,7 +89,7 @@ The `connectionName` property in host.json is a reference to environment configu
 
 If the configured value is both an exact match for a single setting and a prefix match for other settings, the exact match is used. If no value is specified in host.json, the default value is "AzureWebJobsStorage".
 
-##### Identity-based connections (preview)
+##### Identity-based connections 
 
 If you are using [version 2.7.0 or higher of the extension](https://github.com/Azure/azure-functions-durable-extension/releases/tag/v2.7.0) and the Azure storage provider, instead of using a connection string with a secret, you can have the app use an [Azure Active Directory identity](../../active-directory/fundamentals/active-directory-whatis.md). To do this, you would define settings under a common prefix which maps to the `connectionName` property in the trigger and binding configuration.