Use-Git should only validate the current pipeline step

[StartAutomating]

When Use-Git is attempting to determine dynamic parameters, it sometimes needs to determine the current statement without the AST.

This can lead to a caught error, "an empty pipe is not allowed".

These coercion errors should be sidestepped in a few ways:

1. Removing a trailing pipe operator from the command resolution
2. Putting and validation scriptblock creation errors from this point into -Debug
3. Removing them from $error when encountered