update synker config for Gitlab

Gitlab and gitlab-runner were updated but the synker config was missed.

changed milestone to %1.15.0

changed iteration to Big Bang Iterations Aug 10, 2021 - Aug 23, 2021

added statusdoing label

added gitlab gitlabRunner labels

created merge request !760 (merged) to address this issue

mentioned in merge request !760 (merged)

closed with merge request !760 (merged)

mentioned in commit 5df9c63c

removed statusdoing label