fix: properly tokenize command args using shlex.split() for Windows

[tsmithsz]

Problem

1. The bashExecute tool was incorrectly handling command arguments by passing them as a single string for Windows. This caused issues with quoted arguments where commands like git commit -m "test commit" would fail due to improper argument tokenization.

2. The validation checks for windows commands using where fails for built-in windows commands

Solution

1. Modified the command execution to use shlex.split() with the spread operator to properly tokenize arguments
2. Fix windows built-in command validation by using help for checking built-in commands. This reduces constant failures we saw.

Testing

• Tested on unix and windows machine
• Tested commands user previously reported failures for
• Testing was also done by original windows reporters using a local build

License

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.