[applets/notes] Fix drag-and-drop focus stealing

The sticky note widget focuses the text area when dragging desktop icons
over the widget. This can cause the desktop icons to disappear once they
are dropped on the desktop.

BUG: 449711


(cherry picked from commit cd39585e)

applets/notes/package/contents/ui/main.qml

@@ -350,7 +350,6 @@ PlasmaCore.SvgItem {
                 mainTextArea.moveCursorSelection(positionOfDrop(event))
                 mainTextArea.deselect()
             }
-            onDragEnter: mainTextArea.forceActiveFocus()
 
             MouseArea {
                 anchors.fill: parent