uSync push fails for in-use files, but thinks it's OK

[PhyxionNL]

Describe the bug
If you push a file to a destination that's in-use, uSync doesn't report that correctly.

Version (please complete the following information):

• Umbraco Version: 13.3
• uSync Version: 13.2.1
• uSync.Complete Version: 13.1.3

To Reproduce
Steps to reproduce the behavior:

1. Upload a media file that takes some time to download. I recommend an executable file as it's pretty much always locked by Umbraco/IIS process (w3wp).
2. Sync this to destination.
3. Download said file from destination, hopefully from a slow connection so it takes a while.
   Alternatively, write small program that opens the file with FileShare.None on destination, and keep it open so the file is permanently in-use.
4. Make a change in source to this file, and push it from "Media" in Umbraco.
5. uSync says everything is successfully pushed, but it's not as it cannot write the file.

Expected behavior
Give an error that file is in-use / couldn't write it.