Add new function to get indivial test score for aarch64

Add new function to get indivial test score for aarch64

as architecture is not considered as a constraints (unlike scenario or
installer) we need to work on the build tag to retrieve the data

but it is not possible to use regex directly in the API

so retrieveing the accurate results require extra processing
 * based on build_tag, filter the results properly per scenario
 * build a table build_tag time for a given scenario
 * keep only the last 4 results
 * evaluation criteria field

It would simplified if architecture could be declared as a constraint
then querying the resuls will not change and not require intermediate
steps

JIRA: FUNCTEST-880

Change-Id: Id4fe4f56babf0964d41e299905c804e0d837c3d7
Signed-off-by: Morgan Richomme <morgan.richomme@orange.com>