Revert "Merge branch '23638-remove-builds-tab' into 'master'"
Following our discussion in https://gitlab.com/gitlab-org/gitlab-ce/issues/26054 we will revert the removal of builds tab from merge request and commit view from 8.15 as this is usability regression. However, the change will stay on masteras a merge request adding a https://gitlab.com/gitlab-org/gitlab-ce/issues/23785 is slated for 8.16.