Add doctor warning if using ValKey instead of Redis

Overview

In !5032 (merged) we added support to the dependency checker to accept ValKey as a Redis substitute - mainly to ensure support for Fedora, which now installs ValKey by default.

This change was announced in Fedora's Wiki, but users may not have noticed it and just got their Redis replaced with ValKey.

Because we - @gl-dx/developer-tooling - AFAIK don't run Fedora we should probably add a warning indicating to the user to switch to Redis if experiencing misbehaviour. This is relevant as long as https://gitlab.com/groups/gitlab-com/gl-infra/data-access/durability/-/epics/36 isn't solved.

Impacted categories

The following categories relate to this issue:

• gdk-reliability - e.g. When a GDK action fails to complete.
• gdk-usability - e.g. Improvements or suggestions around how the GDK functions.
• gdk-performance - e.g. When a GDK action is slow or times out.

Proposal (optional)

Because we - @gl-dx/developer-tooling - AFAIK don't run Fedora we should probably add a warning indicating to the user to switch to Redis if experiencing misbehaviour. This is relevant as long as https://gitlab.com/groups/gitlab-com/gl-infra/data-access/durability/-/epics/36 isn't solved.

Environment (optional)

• Operating system name: Fedora 41