Reduce IMS Update calls by first checking if entry already up to date

[kwin]

Maybe it is beneficial to first compare the as-is group state with https://adobe-apiplatform.github.io/umapi-documentation/en/api/getUsersByGroup.html or https://adobe-apiplatform.github.io/umapi-documentation/en/api/group.html with the to-be state before updating IMS groups (to speed things up).

However, the additional GET requests to retrieve group information have also throttle limits