Bug: Files that are only referenced using `typeof import(…)` must be added to `OTHER_FILES.txt`

[ExE-Boss]

See DefinitelyTyped/DefinitelyTyped#44805 (specifically https://travis-ci.org/github/DefinitelyTyped/DefinitelyTyped/builds/688383681).

The expected behaviour is that DefinitelyTyped/DefinitelyTyped@06eb285 is not needed when those files are referenced only using typeof import(…).

[sandersn]

Similar to #44