When grouping USD items, make the group name more unique vs other existing group names. This avoid having a chain of group with names almost all the same.
We don't do this for other prims, because too much code, especially unit tests related to materials, assume that the names will have specific pattern.
Add a new utility function is UsdUfe to make a name relatively unique.
Use that function to prepare the group name.
Add a new unit test.
Adjust a ungroup unit test that assumed things about the group name.
When grouping USD items, make the group name more unique vs other existing group names. This avoid having a chain of group with names almost all the same.
We don't do this for other prims, because too much code, especially unit tests related to materials, assume that the names will have specific pattern.