Test that not_standing values are preserved on 'identity edits'
Test that not_standing values are preserved on 'identity edits'

i.e. if you click edit, and save without changing anything, the
not_standing values for that person should be the same afterwards.

We haven't seen this exact problem, but it would be easy to break so it
seems worth having the test.

DemocracyClub/yournextrepresentative,DemocracyClub/yournextrepresentative,DemocracyClub/yournextrepresentative