Reorder associations and validations

app/models/user.rb

@@ -1,9 +1,6 @@
 class User < ApplicationRecord
   belongs_to :account
 
-  has_many :assignments
-  has_many :assigned, through: :assignments, source: :bubble
-
   has_many :sessions, dependent: :destroy
   has_secure_password validations: false
 
@@ -11,6 +8,10 @@ class User < ApplicationRecord
   has_many :projects, through: :accesses
   has_many :bubbles, through: :projects
 
+  has_many :assignments
+  has_many :assigned_bubbles, through: :assignments, source: :bubble
+
+  validates_presence_of :email_address
   normalizes :email_address, with: ->(value) { value.strip.downcase }
 
   scope :active, -> { where(active: true) }