Change config as if the modules defined in config_exclude_modules had been uninstalled

I guess we will need tests for this
Maybe even to update existing ones

But let's first do maual testing.

PS. Roles are also updated at least in drupal 10 where I tested this.

The patch in 8 is a good start, but it is far from complete. It currently does the removing only. It also needs to put the removed config back in a "patch" way, otherwise on an import the removed things will not be added again. I think it would be best to start with a test here.

The test would have a config which changes when a module is excluded. (such as a role having the permission removed)
The test should assert that the permission is not present in the exported config, but when importing the config again the permission should be set again. At the very least. There are other cases we should test too but this would be a good start.

I can confirm patch in #8 only partially fixes it. It's a damned good thing I watch those config diffs like a hawk. 🤣 FWIW, I'm now using https://www.drupal.org/project/config_ignore → and I recommend that anyway as it's targeted to specific configs rather than the whole module.