[ngrams] annotate types of ngrams algorithms

4 jobs for 224-dev-understanding-ngrams in 52 minutes and 15 seconds (queued for 6 seconds)
Status Job ID Name Coverage
  Cabal
passed #16636
cabal

00:21:23

 
  Stack
passed #16637
stack

00:07:27

 
  Bench
manual #16638
allowed to fail manual
bench
 
  Test
passed #16639
test

00:23:24