(PE-37481) Add retry with exponential backoff when error 32 (file in use on windows) occurs

[tlehman]

This PR adds:

• Instructions for running the tests
• A retry loop with exponential backoff (100ms up to 5 times, doubling each time) when there's a system error 32
  • This is to avoid having to make windows-specific code

[tlehman]

Closing this in favor of a retry loop at the pxp-agent level. This logic doesn't belong in leatherman.