testOptions aren't propagated through some of the test methods

[SKaistrenko]

applyTransform relies on testOptions for a parser option.
At the same time defineSnapshotTestFromFixture, defineSnapshotTest, runSnapshotTest (maybe others) don't propagate user-supplied testOptions.

A possible work-around is to run export the parser const from the transformer module, but that limit the ability to use the module with multiple transformers (e.g babylon and ts)