Align instance tagging

[npalm]

Problem

Currently the formatting of tag the instances is not consequent. For example

• ghr:Type
• ghr:environment

Proposal

Format all tags ghr:* with snake case. Any tag namge chaged could cause a breaking tchagen. So there where scale down is depended on case the implementation should be done in two steps. Ensure that the scale down function can handle the old tags as well, to make an update fluent.