PDB-109 Ensure basic_collection tests work on a clean database

Some of the data from previous tests was being leaked. This patch adds a clear
and restart action to the start of the test to ensure there is no existing
data before these tests run.

Signed-off-by: Ken Barber <ken@bob.sh>
Merge pull request #761 from kbarber/ticket/master/PDB-109-fix-ci-errors

PDB-109 Ensure basic_collection tests work on a clean database