title: Grouping an Array by an Object in The Arrays Object -> Vue Storefront
body: <p>Im new at VueSTorefront and i have a Problem at my Project.
  I want to Display the Products in the Cart in an Accordion gruped by their type.
  For this i want to group this Array by their Producttype so i have an Array-&gt;Object with the producttype and an Array with Products which have this Producttype.
  Can someone Help me on this Issue? im struggeling a long time on this issue.</p>
  <p><a href="https://i.stack.imgur.com/2tG9P.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/2tG9P.png" alt="Structure of first Array" /></a></p>