Since the target branch was in a different repository, the action failed
since it couldn't find the reference.
The code here is based on a recent change in Pronto [1] and with a comparison
between the repo.url property of pull_request.head and pull_request.base
to determine if the pull request was created from a forked repository
[1] https://github.com/prontolabs/pronto/commit/4fe28418b6
These lines were added when we were trying the pronto-eslint_npm gem,
which isn't maintained anymore and is not compatible with the latest
Pronto version.
Since we're now using the pronto-eslint gem, and this gem depends on the
eslintrb gem (which includes ESLint), we don't need these lines anymore.
This way developers can run the checks on their machines and using
`bundle exec` we guarantee the right versions of all our gems are being
used; with Hound we can only use the versions supported by their
service.
When including the pronto-erb_lint gem, we're getting errors in
development where our ERB does not follow the conventions Better HTML
expects. Since we only use Better HTML because ERB Lint depends on it,
and right now we are not ready to follow its conventions, we're
disabling it.
Note pronto depends on rugged, which requires CMake and pkg-config to
build the `libgit2` library it depends on. CMake and pkg-config are
installed by default in some GNU/Linux distributions like Ubuntu, but
might not be installed on other systems, so we're adding them as
development dependencies.
