Making Windows compatible

[robertobasile84]

Without this change, hitting the root drive (whatever letter) would case a RangeError: Maximum call stack size exceeded

[thdxr]

@robertobasile84 Thanks for finding this! Left some minor style comments but can get this merged in once those are updated

[jfriend00]

The last solution shown in this stackoverflow post https://stackoverflow.com/a/68977855/816620 is a bit more elegant and would also handle Windows UNC paths (paths that start with \\) that are sometimes used instead of drive letters or paths that don't contain a drive letter, but start with \. That might be better than the regex which only handles drive letters.

[fwang]

This is released in v0.40.6. To update, run:

npm install --save --save-exact @serverless-stack/cli@0.40.6 @serverless-stack/resources@0.40.6

Sorry for the delay @robertobasile84! Thanks again for the help @jfriend00!