.NET 5 startup command guidance

Hello!

We are in the process of upgrading our API to .NET 5. We are able to run everything locally, but running into some issues when deploying to Azure. We specified `DOTNETCORE|5.0` as the `linuxFxVersion`, which seems to match the UI inside the Azure Portal, but the application fails to start.

The diagnostics page of App Service shows errors related to a failed startup command, which shows that the `appsvc/dotnetcore5.0` Docker image does not exist/not specified in the default startup command.

What are we doing wrong? Do we need to use `dotnet publish --self-contained`? If so, can think be documented?

Thank you!