[dfmc-testing] Switch to using methods for the tests as this works.

Using top level init forms did not work.
[dfmc-testing] Disable typist-lambda test as it goes into infinite recursion.
Merge pull request #798 from waywardmonkeys/fix-typist-inference-tests

Fix typist inference tests

Looks good.
Needs further fixing, but thats to be expected (i suppose typist tests should also work on TLFs).