Render labels using Text.QtRendering on OSX

Fonts were looking a bit to thick on when using `Text.NativeRendering`, so using `Text.QtRendering` instead. After this the font weight looks identical to figma (as far as I can see).

In this commit I also changed all `Label`'s to `UM.Label`'s and removed default properties where I could.

CURA-9154

plugins/Marketplace/resources/qml/PackageCard.qml

@@ -29,16 +29,13 @@ Rectangle
 
             anchors.fill: parent
 
-            Label
+            UM.Label
             {
                 id: descriptionLabel
                 width: parent.width
 
                 text: packageData.description
-                font: UM.Theme.getFont("default")
-                color: UM.Theme.getColor("text")
                 maximumLineCount: 2
-                wrapMode: Text.Wrap
                 elide: Text.ElideRight
                 visible: text !== ""
             }