This pull request adds the ability for the `propagation_steps` value
for certain automasking settings to be applied globally instead of
using the per-brush attribute.
Previously, while the flag settings were stored at the brush and global
level, the `propagation_steps` value would always change the brush
attribute even when using the global menu.
Addresses #102377
Pull Request: https://projects.blender.org/blender/blender/pulls/117316