[FIX] account: sequence_id field in account.journal

The sequence_id field can be seen in debug mode but it cannot
be edited.

opw:676223

addons/account/views/account_view.xml

@@ -251,7 +251,7 @@
                                     <group>
                                         <field name="code" attrs="{'readonly': ['|',('type', 'in', ['bank','cash']),('sequence_id','!=',False)], 'required': [('type', 'not in', ['bank', 'cash'])]}"/>
                                         <field name="refund_sequence" attrs="{'invisible': [('type', 'not in', ['sale', 'purchase'])]}"/>
-                                        <field name="sequence_id" required="0" groups="base.group_no_one"/>
+                                        <field name="sequence_id" required="0" attrs="{'readonly': 1}" groups="base.group_no_one"/>
                                         <field name="refund_sequence_id" attrs="{'invisible': ['|',('type', 'not in', ['sale', 'purchase']), ('refund_sequence', '!=', True)]}" required="0" groups="base.group_no_one"/>
                                     </group>
                                     <group>