QmlDesigner: Update Tooltips for Rectangle Section

This patch update tooltip text for Rectangle fields
in Property editor.

Fixes: QDS-9002
Change-Id: I23a9456bb7f4555b42d6a0b6fb5ea8f2d7ddb2cb
Reviewed-by: Mats Honkamaa <mats.honkamaa@qt.io>
Reviewed-by: <github-actions-qt-creator@cristianadam.eu>
Reviewed-by: Thomas Hartmann <thomas.hartmann@qt.io>

share/qtcreator/qmldesigner/propertyEditorQmlSources/QtQuick/RectangleSpecifics.qml

@@ -16,7 +16,10 @@ Column {
         caption: qsTr("Rectangle")
 
         SectionLayout {
-            PropertyLabel { text: qsTr("Fill color") }
+            PropertyLabel {
+                text: qsTr("Fill color")
+                tooltip: qsTr("Sets the color for the background.")
+            }
 
             ColorEditor {
                 backendValue: backendValues.color
@@ -25,6 +28,7 @@ Column {
 
             PropertyLabel {
                 text: qsTr("Border color")
+                tooltip: qsTr("Sets the color for the border.")
                 visible: backendValues.border_color.isAvailable
             }
 
@@ -36,6 +40,7 @@ Column {
 
             PropertyLabel {
                 text: qsTr("Border width")
+                tooltip: qsTr("Sets the border width.")
                 blockedByTemplate: !backendValues.border_width.isAvailable
             }
 
@@ -51,7 +56,10 @@ Column {
                 ExpandingSpacer {}
             }
 
-            PropertyLabel { text: qsTr("Radius") }
+            PropertyLabel {
+                text: qsTr("Radius")
+                tooltip: qsTr("Sets the radius by which the corners get rounded.")
+            }
 
             SecondColumnLayout {
                 SpinBox {