Revert "add fabricators"

This reverts commit 6a02e639d2155c84d502d17cd0baa7dd5a831b98.

Conflicts:
	spec/fabricators/message_fabricator.rb

refs:
https://github.com/iiirc/iiirc/commit/6a02e639d2155c84d502d17cd0baa7dd5a831b98#commitcomment-3233441
Add a fabricator for Message
Add a fabricator for Star
change spec according to a643eff7