Update general-faq.md

[bgulla]

removing notice about mesos & swarm. it's been 6+ years since 2.0 was released, time to move on.

Fixes #[issue_number]

Reminders

• See the README for more details on how to work with the Rancher docs.

• Verify if changes pertain to other versions of Rancher. If they do, finalize the edits on one version of the page, then apply the edits to the other versions.

• If the pull request is dependent on an upcoming release, make sure to target the release branch instead of main.

Description

Comments

[martyav]

I would suggest also removing from versioned_docs/version-2.6/faq.md, versioned_docs/version-2.7/faq/general-faq.md and /version-2.8/general-faq/faq.md. We can leave it in the earliest versioned docs files, since that's where it would most likely come up as a question (if it comes up as a question).