Build failing: 'System.ReadOnlySpan'

[KazeEnji]

Hello,

I'm attempting to use Codeception against Rubeus and I'm running into this error:

Could not compile solution: Method not found: 'System.ReadOnlySpan1<Char>Microsoft.IO.Path.GetFileName(System.ReadOnlySpan1<Char>)'.

My research shows that this is due to a breaking change that happened with MSBuild at version 4.0.5 but I have the proper version installed per the github instructions: 3.9.0. I don't know what to change about it. I'm running Codeception with the debug switch and that doesn't seem to do anything either.