fix: populate themes with prev val on person form

Resolves #66

people/forms.py

@@ -107,6 +107,8 @@ class PersonAnswerSetForm(forms.ModelForm, DynamicAnswerSetBase):
         self.instance.person_id = self.initial['person_id']
         if commit:
             self.instance.save()
+            # Need to call same_m2m manually since we use commit=False above
+            self.save_m2m()
 
         if commit:
             # Save answers to relationship questions

people/models/person.py

@@ -214,7 +214,6 @@ class PersonAnswerSet(AnswerSet):
             'replaced_timestamp',
             'person_id',
             'question_answers',
-            'themes',
         }
 
         def field_value_repr(field):