Add links to NETSDK1150 and NETSDK1151 messages

[dsplaisted]

Add links to error messages generated when there's a mismatch between self-contained values when an Exe project references another Exe.

Currently these links point to the breaking change documentation here: https://docs.microsoft.com/en-us/dotnet/core/compatibility/sdk/5.0/referencing-executable-generates-error

This should make it a lot easier for people that hit this error message to turn it off.

[ghost]

I couldn't figure out the best area label to add to this PR. If you have write-permissions please help me learn by adding exactly one area label.

[beatcracker]

Any chance of backporting this to .NET 5 SDK? The fe6e411 is tagged with v6.0.100-rc.2.21505.11 and v6.0.100-rc.1.21458.71.

I'm on the 5.0.402 and the links are not there:

/usr/share/dotnet/sdk/5.0.402/Sdks/Microsoft.NET.Sdk/targets/Microsoft.NET.Sdk.targets(993,5):
Error NETSDK1150: The referenced project '../foo/bar.csproj' is a non self-contained executable. 
A non self-contained executable cannot be referenced by a self-contained executable.

This message above is from the container-based build using .NET SDK 5 image:

• mcr.microsoft.com/dotnet/sdk:5.0-buster-slim
• sha256:5d6aff01076f269ecf5b9d9e5d708d1cb21636636f54c47d929efde9e89bb197