Shim Improvements

[Bios-Marcel]

Scoop is currently adding shim improvements, namely:

#5840

and

ScoopInstaller/Scoop@353137f

These two changes should be added here as well. For the GUI shim, we'll however compile separate shims to avoid bugs.

For the former, we'll try to do this in a backwards compatible way. But overall this is a good change, as this will prevent system breakages through often accessing sensitive variables such as the PATH.