Make header of detail page depend on header of origin

It's the same as the list of packages you came from, now.

Contributes to issue CURA-8565.

plugins/Marketplace/resources/qml/PackageDetails.qml

@@ -12,6 +12,7 @@ Item
 {
     id: detailPage
     property var packageData: packages.selectedPackage
+    property string title: catalog.i18nc("@header", "Package details")
 
     RowLayout
     {
@@ -49,7 +50,7 @@ Item
             Layout.alignment: Qt.AlignVCenter
             Layout.fillWidth: true
 
-            text: "Install Plug-ins" //TODO: Depend on package type, and translate.
+            text: detailPage.title
             font: UM.Theme.getFont("large")
             color: UM.Theme.getColor("text")
         }

plugins/Marketplace/resources/qml/Packages.qml

@@ -19,8 +19,6 @@ ListView
     Component.onCompleted: model.updatePackages()
     Component.onDestruction: model.abortUpdating()
 
-    //ScrollBar.vertical.policy: ScrollBar.AlwaysOff
-
     spacing: UM.Theme.getSize("default_margin").height
 
     section.property: "package.sectionTitle"
@@ -88,6 +86,7 @@ ListView
         PackageDetails
         {
             packageData: packages.selectedPackage
+            title: packages.pageTitle
         }
     }