Use of node group assets relies on a few properties written to asset
meta-data for proper filtering of assets in menus (add modifier menu,
node add menu, 3D view menus for tools). Currently these meta-data
properties are written when updating their source properties and when
saving the file. That means they *aren't* written when marking a group
as an asset, which is necessary because the meta-data doesn't exist
before when the group isn't an asset. Currently users have to save the
file to update menus in this case, which isn't intuitive.
As a fix, call the function to write the meta-data when marking a
data-block as an asset.
Pull Request: https://projects.blender.org/blender/blender/pulls/112743