Fixing coverage tool. It had double 'contrib' on script path. (#1568)

* Fixing coverage tool. it had double 'contrib' on script path.

* Use rel dir location.

Author: n3wscott

contrib/hack/coverage.sh

@@ -17,7 +17,7 @@
 set -o nounset
 set -o errexit
 
-ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/../.." && pwd)"
 . "${ROOT}/contrib/hack/utilities.sh" || { echo 'Cannot load utilities.'; exit 1; }
 
 function usage() {