Changing the image size from "pixels" to "cm" does not save user choice

[vladz99]

Describe the bug
When you change the file size from "pixels" to "cm", when you re-open it, "pixels" is selected again".

To Reproduce
Steps to reproduce the behavior:

1. Open the image
2. Select "image" from the menu
3. Select "image size"
4. Change the image size from "pixels" to "cm"
5. Close this window and open it again

Expected behavior
When you re-open it, the "cm" option remains selected.

Screenshots

Desktop (please complete the following information):

• OS: [Windows 10]
• Version [1.6.6]

Additional context
Add any other context about the problem here.