do not run tests on TravisCI which are run as GitHub Actions
do not run tests on TravisCI which are run as GitHub Actions

All tests except for BrowserStack tests were executed both on TravisCI
and as GitHub Actions. As GitHub Actions has been prooven to be stable
we can remove duplicated tests now and only run BrowserStack tests on
TravisCI. We should migrate them to GitHub Actions as well in a
follow-up merge request to reduce complexity.

jelhan/croodle,jelhan/croodle,jelhan/croodle