Update GitVersionTask when compatibility issue is fixed

[rose-a]

There is a compatibility issue with GitVersionTask in combination with MSBuild 16.5 and .NET Core 3.1.200, which prevents building the project.

The build in GitHub actions works because the version vars get injected via environment.

Must be updated as soon as the fix is released.

[sungam3r]

The build in GitHub actions works because the version vars get injected via environment.

What version vars?

[rose-a]

The first job in the GitHub workflow generates the GitVersion info using gitversion.tool (see here).

Those are saved as artifact and injected into the build environment in the following jobs.

This circumvents a concurrency problem in GitVersionTask by picking them up here and saves resources.

If you build the project in your devenv, the GitVersion_SemVer evironment variable is very likely not set, then GitVersionTask is executed within the build process.