Announcing new supported formats for Azure Schema Registry

ashish-chhabria I'm trying to test the Protobuf support in Azure schema registry, however executing [PutSchema](https://learn.microsoft.com/rest/api/eventhub/put-schema) returns the following error:

{"error":{"code":"InvalidRequest","message":"Protobuf schema support is currently disabled. ..."}}

How do I enable Protobuf support in my schema registry to test this out?

I also noticed that the official [Azure SDK package for .NET](https://www.nuget.org/packages/Azure.Data.SchemaRegistry/) doesn't currently support Protobuf, even in beta package version. Is it possible to push the beta version of Azure.Data.SchemaRegistry where this support [was added](https://github.com/Azure/azure-sdk-for-net/blob/dd70ed4fcc1a9e5ca6282b368b762c941638402d/sdk/schemaregistry/Azure.Data.SchemaRegistry/src/SchemaFormat.cs#L18)?