Cannot create new user with a Google account that has an empty family name field

[anncatton]

To reproduce:

• using a Google account that does NOT have an existing user in Ego, update your Google Personal Info -> Name info to leave the Last Name field blank:
  Private Zenhub Image

• log into Ego with this Google account

Result: After successfully authenticating with Google oauth, the /ego-token endpoint will respond with a 400 error:
Private Zenhub Image

Cause:
The CreateUserRequest.builder call fails because it is expecting a value for the family_name field.

Solution:
Some of the other providers do not guarantee this field exists so their builder calls include a default empty string value on creation. Update the create user flow so that this is the default approach.