validate incoming_auth_username and password (#1465)

* validate gateways auth usernames and passwords

app/models/gateway.rb

@@ -312,8 +312,11 @@ def normalize_host(value)
 
   validates :diversion_domain, presence: true, if: proc { diversion_send_mode_id == 2 }
 
+  validates :auth_user, :auth_password, format: { without: /\s/, message: 'must contain no spaces' }
+
   validates :incoming_auth_username, presence: true, if: proc { incoming_auth_password.present? }
   validates :incoming_auth_password, presence: true, if: proc { incoming_auth_username.present? }
+  validates :incoming_auth_username, :incoming_auth_password, format: { without: /\s/, message: 'must contain no spaces' }
 
   validates :transit_headers_from_origination, :transit_headers_from_termination,
             format: { with: /\A[a-zA-Z\-\,\*]*\z/, message: 'Enter headers separated by comma. Header name can contain letters, * and -' }