Install-BinFile should throw an exception when used on any non-executable

### What You Are Seeing?
Install-BinFile acceppts any file in `-Path` parameter
When a .ps1-script is given the execution of the generated shim crashes.

### What is Expected?
unsupported filetypes/non-executables should be rejected

### How Did You Get This To Happen? (Steps to Reproduce)
see minimal sample at gist
GIST LINK https://gist.github.com/mwallner/3ff3de99195feb62bfa65092d56296cd

Start with the minimal sample in the linked gist and trace the Install-BinFile entry point that accepts the -Path parameter. Confirm how a .ps1 file reaches shim generation, then make unsupported or non-executable files raise an exception and verify that the sample no longer creates a crashing shim.

Written by the indexing model from the issue text.