Switch out shop icon

The sourceSize needs to be adjusted because this is an SVG that we don't necessarily want to stretch but just want to render directly at the correct size.

Contributes to issue CURA-7071.

plugins/Toolbox/resources/images/shop.svg

@@ -0,0 +1,3 @@
+<svg xmlns="http://www.w3.org/2000/svg" width="24" height="24">
+    <path d="M19,3H5A2.9,2.9,0,0,0,2,6V9a3.9,3.9,0,0,0,2,3.4V22H20V12.4A3.9,3.9,0,0,0,22,9V6A2.9,2.9,0,0,0,19,3ZM10,5h4V9a2,2,0,0,1-4,0ZM4,9V5H8V9A2,2,0,0,1,4,9ZM18,20H14V15H10v5H6V13a3.7,3.7,0,0,0,3-1.4A3.7,3.7,0,0,0,12,13a3.7,3.7,0,0,0,3-1.4A3.7,3.7,0,0,0,18,13ZM20,9a2,2,0,0,1-4,0V5h4Z" />
+</svg>

plugins/Toolbox/resources/qml/components/ToolboxHeader.qml

@@ -1,4 +1,4 @@
-// Copyright (c) 2018 Ultimaker B.V.
+// Copyright (c) 2020 Ultimaker B.V.
 // Toolbox is released under the terms of the LGPLv3 or higher.
 
 import QtQuick 2.10
@@ -92,11 +92,12 @@ Item
         Image
         {
             id: cloudMarketplaceButton
-            source: "../../images/marketplace.png"
+            source: "../../images/shop.svg"
             height: 45
             width: height
+            sourceSize.width: width
+            sourceSize.height: height
             //width: UM.Theme.getSize("toolbox_header_tab").width
-            mipmap: true
             fillMode: Image.PreserveAspectFit
             MouseArea
             {