.travis.yml for Haskell ghc-8.4.3 build on macOS

This is a request for a little help. I have a .travis.yml file written to build a repo with Haskell’s stack using ghc-8.4.3.

It fails at the last step because I’m apparently in the wrong directory. I tried the obvious stuff but do not see the issue.

Any pointers would be greatly appreciated.

See https://api.travis-ci.org/v3/job/431239222/log.txt for the latest build fail. I know the repo builds successfully by hand.

This is fixed with a single cd command in the install block.