Allow the user to change folder for .bkp files

[SimonDam]

• I agree to follow the Code of Conduct that this project adheres to.
• I have searched the issue tracker for a feature request that matches the one I want to file, without success.

Is your feature request related to a problem? Please describe.
I would like to have my .drawio files part of my versoin control, and while I could add the .bkp files to the ignore, I would prefer to have them in another location outside the repo.

Describe the solution you'd like
A place to choose a filepath for placing the generated .bkp files.

Describe alternatives you've considered
Adding .bkp to my ignore.

Additional context
No