I've tagged and pushed the base image to base:latest (base:20250211.1 has been
built by jenkins).

```
tony@kessel:~/work/inria/repo/swh/sysadm-environment/swh-apps (master) $ docker tag container-registry.softwareheritage.org/swh/infra/swh-apps/base:20250211.1
container-registry.softwareheritage.org/swh/infra/swh-apps/base:latest
tony@kessel:~/work/inria/repo/swh/sysadm-environment/swh-apps (master) $ docker push container-registry.softwareheritage.org/swh/infra/swh-apps/base:latest
The push refers to repository [container-registry.softwareheritage.org/swh/infra/swh-apps/base]
24f1bb282167: Layer already exists
5f70bf18a086: Layer already exists
8b5b3a8db38d: Layer already exists
cc8c3d91a205: Layer already exists
29f95138ec86: Layer already exists
ca3e6f391164: Layer already exists
8f0805620093: Layer already exists
dafb8aed9f7f: Layer already exists
41d4dc7516bb: Layer already exists
c0f51bbdc37d: Layer already exists
91b542912d12: Layer already exists
latest: digest:
sha256:54f4fa022728762166b220adcd6e5d35ef4ef3fb1332e1d2a7ae95c869cee21e size:
2637
```

Refs. sysadm-environment#5560

Refs. sysadm-environment#5560

Let it be part of the requirements*.txt (thus the requirements-frozen.txt) instead.

Related to sysadm-environment#5387

The environment variable SWH_LOG_LEVEL will be declared in swh-charts.

Refs. swh/infra/sysadm-environment#5321

Refs. swh/infra/sysadm-environment#5179

In terms of docker build for swh-scheduler app.

Refs. sysadm-environment#5035

Related to sysadm-environment#4811

Related to T4144

It makes impossible to run apt after, which can make the debugging
complicated if some packages need to be added during a debug session