improve mgmt plane template (Azure#28820)

Author: Yao725

eng/templates/Azure.ResourceManager.Template/CHANGELOG.md

@@ -2,6 +2,14 @@
 
 ## 1.0.0-beta.1 (Unreleased)
 
+### General New Features
+
+    - Support MSAL.NET, Azure.Identity is out of box for supporting MSAL.NET
+    - Support [OpenTelemetry](https://opentelemetry.io/) for distributed tracing
+    - HTTP pipeline with custom policies
+    - Better error-handling
+    - Support uniform telemetry across all languages
+
 This package follows the [Azure SDK Design Guidelines for .NET](https://azure.github.io/azure-sdk/dotnet_introduction.html) which provide a number of core capabilities that are shared amongst all Azure SDKs, including the intuitive Azure Identity library, an HTTP Pipeline with custom policies, error-handling, distributed tracing, and much more.
 
 This is a Public Preview version, so expect incompatible changes in subsequent releases as we improve the product. To provide feedback, please submit an issue in our [Azure SDK for .NET GitHub repo](https://github.com/Azure/azure-sdk-for-net/issues).

eng/templates/Azure.ResourceManager.Template/src/autorest.md

@@ -9,7 +9,7 @@ csharp: true
 library-name: ProviderShortName
 namespace: Azure.ResourceManager.ProviderShortName
 require: https://raw.githubusercontent.com/Azure/azure-rest-api-specs/main/specification/ProviderNameLowercase/resource-manager/readme.md
-output-folder: Generated/
+output-folder: $(this-folder)/Generated
 clear-output-folder: true
 skip-csproj: true
 tagPrefix SwaggerVersionTag