Clarify what objects toContain and toContainEqual can be used on (#4307)
Clarify what objects toContain and toContainEqual can be used on (#4307)

This is just a documentation change to clarify that `toContain` and `toContainEqual` matchers work on arrays and strings (but not objects) rather than the more ambiguous "list".

This also adds consistency, since all other api method docs refer to "arrays", rather than "lists".
ide/jest,facebook/jest,bookman25/jest,bookman25/jest,facebook/jest,facebook/jest,ide/jest,ide/jest,cpojer/jest,bookman25/jest,cpojer/jest,cpojer/jest