https://gitlab.com/gitlab-org/gitlab/-/merge_requests/52750 broke
consolidated storage settings because it was scanning storage-specific
settings. For example, let's say you had:

```yaml
object_store:
    enabled: true
    objects:
        artifacts:
            enabled: false

artifacts:
    enabled: true
```

In `1_settings.rb`, `ObjectStoreSettings#legacy_parse!` will
automatically add default `object_store` settings to the
storage-specific settings:

```yaml
artifacts:
    enabled: true
    object_store:
        enabled: false
        ...
```

As seen above, `artifacts.object_store.enabled` defaults to `false`, so
the check introduced in
https://gitlab.com/gitlab-org/gitlab/-/merge_requests/52750 would mean
that object storage would never be enabled unless storage-specific
settings were also enabled.

The right fix: skip parsing of consolidated settings only if the object
type has explicitly disabled it in the consolidated settings. In the
example above, this means we check the parameter in
`object_store.objects.artifacts.enabled`, which overrides the default
consolidated settings.

This should fix https://gitlab.com/gitlab-org/gitlab/-/issues/233826.