Add Rook maintainer Josh Hoblitt and remove previous Rook maintainers

[travisn]

Checklist for maintainer updates

Link to Rook maintainers documentation: https://github.com/rook/rook/blob/master/OWNERS.md#maintainers

• You've provided a link to documentation where the project has approved the maintainer changes.
• The maintainer(s) also created or updated their LFX Individual Dashboard profile.
• You've sent an email with the list of email address(es) to cncf-maintainer-changes@cncf.io for invitations to Service Desk and mailing lists. You can just mark this complete if you are only removing people.
• Optional: You've also sent a PR with affiliation updates to cncf/gitdm.

[riaankleinhans]

@jhoblitt can you please update https://github.com/rook/.project/blob/main/maintainers.yaml ?

Rook have been automated via the .project repo. Once that file update is merged access the CNCF service desk and project maintainers mailing list would be updated on the next automation run.

The file you updated in the PR would shortly be replaced with an automation pulling form the .project repos.