fix(tf2_gnn/models/*): let __init__ pass extra kwargs to super()

[mmjb]

This fixes #39 by passing through the new disable_tf_function_build (and potentially any future new constructor args) to the super class.

[pashminacameron]

Thanks, this works. I've tested it now. Any classes that derive from GraphTaskModel in code using tf2-gnn also need to be updated, so we may want to note this in the versioning.