[FIX] purchase: not setting context is not empty context

Previous versions of this action had a context. It was removed at odoo/odoo@2d3e6d7383aaa3c1589f22
Set explicitly an empty context to force the removal when upgrading the module. Fine tunning of odoo/odoo@93465630090e2c42

closes odoo/odoo#36007

Signed-off-by: Martin Trigaux (mat) <mat@odoo.com>

addons/purchase/views/purchase_views.xml

@@ -391,6 +391,7 @@
             <field name="res_model">purchase.order</field>
             <field name="view_mode">tree,kanban,form,pivot,graph,calendar,activity</field>
             <field name="domain">[]</field>
+            <field name="context">{}</field>
             <field name="search_view_id" ref="view_purchase_order_filter"/>
             <field name="help" type="html">
               <p class="o_view_nocontent_smiling_face">
@@ -411,6 +412,7 @@
             <field name="res_model">purchase.order</field>
             <field name="view_mode">tree,kanban,form,pivot,graph,calendar,activity</field>
             <field name="domain">[('state','in',('purchase', 'done'))]</field>
+            <field name="context">{}</field>
             <field name="search_view_id" ref="view_purchase_order_filter"/>
             <field name="help" type="html">
               <p class="o_view_nocontent_smiling_face">