Update CHANGELOG.md for #8919

CHANGELOG.md

@@ -22,7 +22,8 @@ IMPROVEMENTS:
 * dependencies: upgrading to `v0.13.0` of `github.com/hashicorp/go-azure-helpers` [GH-9191]
 * dependencies: upgrading to `v0.14.0` of `github.com/tombuildsstuff/giovanni` [GH-9189]
 * storage: upgrading the Data Plane API's to API Version `2019-12-12` [GH-9192]
-* `app_service` support `v5.0` for the `dotnet_framework_version` [GH-9251]
+* `azurerm_app_service` support `v5.0` for the `dotnet_framework_version` [GH-9251]
+* `azurerm_cosmosdb_account` - support for `key_vault_key_id` allowing use of Customer Managed Keys [GH-8919]
 * `azurerm_linux_virtual_machine` - support for managed boot diagnostics by leaving the `storage_account_uri` property empty [GH-8917]
 * `azurerm_linux_virtual_machine_scale_set` - support for managed boot diagnostics by leaving the `storage_account_uri` property empty [GH-8917]
 * `azurerm_log_analytics_workspace` - support for the `internet_ingestion_enabled` and `internet_query_enabled` properties [GH-9033]