tests: Only re-run unit-tests if not initially running as root
tests: Only re-run unit-tests if not initially running as root

Don't run the unit-tests twice if the user that invokes the tests is
already root since both runs would be running as `root`.

Also, ensure the HTML report generated by test_html_coverage() is
readable by all users.

Fixes #496.

Signed-off-by: James O. D. Hunt <348fbaadfbada55ea105602bf5609e23ac1c4898@intel.com>

devimc/runtime,devimc/runtime,clearcontainers/runtime,clearcontainers/runtime,chavafg/runtime,chavafg/runtime