[IMP] account: removed demo data about unexisting field, causing a warning.

addons/account/demo/account_bank_statement.xml

@@ -7,7 +7,6 @@
             <field name="period_id" ref="account.period_5"/>
             <field name="date" eval="time.strftime('%Y')+'-01-01'"/>
             <field name="user_id" ref="base.user_demo"/>
-            <field name="reference_type">none</field>
             <field name="name">BNK/2014/001</field>
             <field name="balance_end" eval="2040.0"/>
             <field name="company_id" ref="base.main_company"/>