The inheritance test depends on the objects being actively destroyed.
Currently this happens in a two step process, where first the C#
object is collected from the GC. As this happens in a separate thread,
we schedule a callback to run in the main loop to actually unref the
EO object.

This commit adds more iterations to make sure the EO of the parent is
unref'd and releases the child.

This should be the last C#-related CI test failure

Ref T8313