[FIX] account: allow to change currency when posted before

There is no reason to forbid changing the currency when a move has been
posted before.
Was introduced in [1] without reason.

[1] https://github.com/odoo/odoo/commit/d1bbf11af27e4ce12b025ef22e397302ee6336c2

closes odoo/odoo#73623

X-original-commit: 9b0578766709b27c91d85bf6246b4bc5e43ca27d
Signed-off-by: Laurent Smet <smetl@users.noreply.github.com>
Signed-off-by: William André (wan) <wan@odoo.com>

addons/account/views/account_move_views.xml

@@ -821,7 +821,7 @@
                                         groups="base.group_multi_currency"> in </span>
                                     <field name="currency_id"
                                         groups="base.group_multi_currency"
-                                        attrs="{'readonly': [('posted_before', '=', True)]}"/>
+                                        attrs="{'readonly': [('state', '!=', 'draft')]}"/>
                                 </div>
                             </group>
                         </group>