tests: E2E tests disabled locally by default
tests: E2E tests disabled locally by default

* Disables E2E tests locally by default. They can still be run by
  setting E2E_WEBDRIVER_BROWSERS.

Signed-off-by: Sami Hiltunen <ebafb54bedf33e7dd12950a4634d6a0f6ba63e44@cern.ch>

inspirehep/invenio-accounts,inveniosoftware/invenio-accounts,inveniosoftware/invenio-accounts,inspirehep/invenio-accounts,inspirehep/invenio-accounts,inveniosoftware/invenio-accounts,tiborsimko/invenio-accounts,tiborsimko/invenio-accounts,tiborsimko/invenio-accounts