[PD-641] Ensure that a user without companies does not belong to the Employer group

~~The reason for so many other files being changed is that I also went ahead and moved the appropriate seo tests from mydashboard to seo and removed empty modules and objects that didn't belong in mydashboard. I also had to update some of the factories in order to get them to work properly (forien key and unique constraints).~~ 

Too many weird things were happening, so I decided to keep it simple instead.