SocialProfileFieldsOverride doesn't check for group_profile_names_image existance

Problem

The SocialProfileFieldsOverride class adds the field_profile_nick_name to the group_profile_names_image group. However, if that group is not present then the override will cause a group with malformed properties to be created which crashes the field_group module.

This makes it impossible for a user to edit their profile.

Solution

Only override the configuration if the field is actually present.