Switch from Redis to Valkey and add Healthchecks

[cimnine]

Related Issue: n/a

New Behavior

This PR removes the non-free Redis and uses Valkey instead, which is the FOSS fork of Redis backed by the Linux Foundation.

Additionally, it adds healthchecks to both instances and also to the postgres db.

Contrast to Current Behavior

We suggest our users to use proprietary software.

Discussion: Benefits and Drawbacks

I wasn't sure whether we should rename any reference to the term redis, which is a trademark. But this would lead to problems when migrating. I'm not even sure if a Docker volume can even be renamed.

Should we decide to not switch to Valkey just now, we should at least add the healthchecks. (They work for redis as well, just with redis-cli instead of valkey-cli of course.)

Regarding We suggest our users to use proprietary software.:
The irony that this project is called netbox-docker, and Docker is a proprietary software, is not entirely lost on me. Today, I would probably call the project netbox-container. We could perhaps even rename the project, as the relevant container repositories don't contain the term netbox-docker. But that's something for another time.

Changes to the Wiki

n/a

Proposed Release Note Entry

Replacing Redis with Valkey
Adding healthchecks to Valkey and PostgreSQL

Double Check

• I have read the comments and followed the PR template.
• I have explained my PR according to the information in the comments.
• My PR targets the develop branch.

[tobiasge]

The Redis containers in docker-compose.test.yml should also be updated to Valkey.

[Fredouye]

Hi

netbox-docker release 3.0.0 is using Valkey 8.0, which is still a release candidate : https://github.com/valkey-io/valkey/releases

docker.io/valkey/valkey:8.0-alpine points to valkey/valkey:8.0.0-rc2-alpine3.20

Shouldn't Netbox use Valkey 7.x in the meantime ?