Fixed windows backup filename - swapped colon in timestamp to hyphen to handle windows filesystems

[snipe]

On some Windows filesystems, adding the customization of the "manual" passing of the timestamp in the filename so we can show manually initiated backups, manually uploaded backups, etc with a H:i:s part of the filename seems like it was causing some issues on some windows machines, causing manual backups to fail with errors. This should solve those scenarios.

[what-the-diff]

PR Summary

• Modified Filename Option in Backups
  In the settings control section, there has been a change to the way backup files are named. Instead of generic names, backup files will now include the exact date and time they were created. This will make it much easier to identify and manage these files in the future.