For consistency with other make tasks, add "." taks for flake8, configs-check and metadata-check make targets / tasks.
For consistency with other make tasks, add "." taks for flake8, configs-check
and metadata-check make targets / tasks.

Those targets don't depend on any other target and can be used directly,
speeding up the process.

pidah/st2contrib,armab/st2contrib,tonybaloney/st2contrib,StackStorm/st2contrib,pidah/st2contrib,StackStorm/st2contrib,pearsontechnology/st2contrib,armab/st2contrib,tonybaloney/st2contrib,armab/st2contrib,pearsontechnology/st2contrib,pearsontechnology/st2contrib,tonybaloney/st2contrib,psychopenguin/st2contrib,psychopenguin/st2contrib,pidah/st2contrib,pearsontechnology/st2contrib,StackStorm/st2contrib