Build time Source Link doesn't understand git submodule URL with "@", which is used by AzDO UI.

[chuckries]

We have a repo with a submodule with a url in the form of <account>@dev.azure.com/<account>/<project>/<_git>/<repo>. In the .gitmodules file it appears as this:

[submodule "<path>"]
	path = ...
	url = https://<account>@dev.azure.com/<account>/<project>/_git/<repo>
        ...

The main repo is also Azure Dev Ops, and references <PackageReference Include="Microsoft.SourceLink.Vsts.Git" Version="1.0.0-beta-63127-02" PrivateAssets="All" />.

After the submodule is restored, Microsoft.SourceLink.Vsts.Git doesn't understand the submodule URL and produces the following build error:
.nuget\packages\microsoft.sourcelink.common\1.0.0-beta-63127-02\build\Microsoft.SourceLink.Common.targets(40,5): error : SourceRoot.SourceLinkUrl is empty: '<path>'

The specified URL was originally used because it is shown in the Azure Dev Ops "clone repo" UI:

Changing the submdoule URL to a <account>.visualstudio.com style URL resolves the issue.