tests: mocks addition

Signed-off-by: Kamil Neczaj <kamil.neczaj@cern.ch>
helpers: events checker tests

* Detailed description formatted as a bullet list (using present tense).

Signed-off-by: Kamil Neczaj <kamil.neczaj@cern.ch>
global: karma conf updated

Signed-off-by: Kamil Neczaj <kamil.neczaj@cern.ch>
tests: facet filter tests

Signed-off-by: Kamil Neczaj <kamil.neczaj@cern.ch>