LC Mapper adding member_of > Group to Activity

[kkdavis14]

fall out from https://git.yale.edu/LUX/unit-data/issues/86

https://lux-byunit1.collections.yale.edu/data/activity/81f4138f-febb-4ec0-9361-da01ebf5c939

Reconciliation to LC is fine, member_of Groups on Activities is not.

LUX isn't rendering this, probably because the template isn't set up like that, good, but want to detect and reroute.