Improve compatibility with built-in container support of .NET SDK

[tmds]

The SDK adds support for building Docker images: https://devblogs.microsoft.com/dotnet/announcing-builtin-container-support-for-the-dotnet-sdk.

It also uses properties from the .NET project files.

They are defined in https://github.com/dotnet/sdk-container-builds/blob/main/docs/ContainerCustomization.md, and dotnet/sdk-container-builds#11.

We should use the same properties, where it makes sense.

Property	sdk-container-builds	build-image
ContainerBaseImageName
ContainerBaseImageTag
ContainerBaseImage	X	X
ContainerImageName	X	X
ContainerImageTag	X	X
ContainerWorkingDirectory	X	X
ContainerEntrypoint	X
ContainerCommand	X
ContainerPort	X	X
ContainerEnvironmentVariable	X	X
ContainerLabel	X	X
ContainerUser
ContainerGroup