In terms of docker build for swh-scheduler app.

Refs. sysadm-environment#5035

Refs. swh/infra/sysadm-environment#5030

Otherwise, it stops as soon as it starts and we cannot connect to it.

Refs. swh/infra/sysadm-environment#5030

It's needed for the gitlab-ci experiment.

Refs. swh/infra/sysadm-environment#4974

Refs. swh/infra/sysadm-environment#5030

This is a deployment toolbox. For starters, it will ease the registering of new
scheduler task type.

Refs. sysadm-environment#5030