In GitLab EE, a GitLab instance can be read-only (e.g. when it's a Geo
secondary node). But in GitLab CE it also might be useful to have the
"read-only" idea around. So port it back to GitLab CE.
Also having the principle of read-only in GitLab CE would hopefully
lead to less errors introduced, doing write operations when there
aren't allowed for read-only calls.
Closesgitlab-org/gitlab-ce#37534.
This is useful for when runner is bundled with gitlab, like in a kubernetes stack, and we want the runner to be able to
register with gitlab as soon as they both come up.
This enables following cops:
Check for useless access modifiers
Lint/UselessAccessModifier
Checks for attempts to use `private` or `protected` to set the
visibility of a class method, which does not work.
Lint/IneffectiveAccessModifier
This also disables two false possitives in concerns.
This adds a ability to use multiple different authentication token
fields in other models. From now on it is necessary to add
authentication token field manually in each class that implements this
mixin.
