Remove gitdm legacy jobs
The jobs are in-tree now, remove them.
Depends-On:
name: openstack-infra/gitdm
templates:
- system-required
- check:
- jobs:
- - legacy-gitdm
- gate:
- jobs:
- - legacy-gitdm
- periodic:
- jobs:
- - legacy-periodic-gitdm
- project:
name: openstack-infra/glean
