Add new team labels to guidebook

https://guidebook.devops.uis.cam.ac.uk/en/latest/reference/gitlab-labels/#teams lists the team labels we have. At least teamJackson, teamDrupal, teamHamilton, teamIdentity and teamHR Systems aren't on that list and needs adding.

For consistency, teamJackson, teamHamilton and teamDrupal should share the colour for other team:: labels like teamAuthentication, teamCloud, teamDevOps, teamHR Systems and teamIdentity