Refactor Expander.TryExecuteWellKnownFunction

[YuliiaKovalova]

Refactor candidate

I have stumbled upon the piece of code and suggest to rethink it:

msbuild/src/Build/Evaluation/Expander.cs

Line 3643 in 28f488a

 private bool TryExecuteWellKnownFunction(out object returnVal, object objectInstance, object[] args) 

It contains code duplications and it's current size poorly manageable.