[IMP] stock: Add product category groupby for inventory adjustment

Add a group by product categories in the stock.quant.

Part of task-2985735

closes odoo/odoo#106396

Signed-off-by: Arnold Moyaux (arm) <arm@odoo.com>

addons/stock/views/stock_quant_views.xml

@@ -46,6 +46,7 @@
                 </group>
                 <group expand='0' string='Group by...'>
                     <filter string='Product' name="productgroup" context="{'group_by': 'product_id'}"/>
+                    <filter string='Product Category' name="productcategorygroup" context="{'group_by': 'product_categ_id'}"/>
                     <filter string='Location' name="locationgroup" domain="[]" context="{'group_by': 'location_id'}"/>
                     <filter string='Storage Category' name="storagecategorygroup" domain="[]" context="{'group_by': 'storage_category_id'}"/>
                     <filter string='Owner' name="owner" context="{'group_by': 'owner_id'}" groups="stock.group_tracking_owner"/>