[Feature Request] Error handling for SDK vs nonSDK

[stefanushinardi]

The request is to provide compile error message when an isolated app reference in-process SDK.

[fabiocav]

This property is set in the Functions SDK and we should be able to evaluate that in the isolated worker SDK : https://github.com/Azure/azure-functions-vs-build-sdk/blob/32ebc25b282fe08ebb283178150450755f2d1044/src/Microsoft.NET.Sdk.Functions.MSBuild/Targets/Microsoft.NET.Sdk.Functions.props#L15