* TextCatParametricAttention.v1: set key transform dimensions
This is necessary for tok2vec implementations that initialize
lazily (e.g. curated transformers).
* Add lazily-initialized tok2vec to simulate transformers
Add a lazily-initialized tok2vec to the tests and test the current
textcat models with it.
Fix some additional issues found using this test.
* isort
* Add `test.` prefix to `LazyInitTok2Vec.v1`
Daniël de Kok