[applets/systemtray] Strip mnemonic ampersand from entry config tooltip

Some applet config titles contain ampersands for mnemonic purposes. PC3.ToolTip filters them out but QQC2.Tooltip does not, so they are visible in the system tray config window.

BUG: 437605

applets/systemtray/package/contents/ui/ConfigEntries.qml

@@ -284,7 +284,9 @@ ColumnLayout {
                         onClicked: configureAction.trigger()
 
                         QQC2.ToolTip {
-                            text: parent.Accessible.name
+                            // Strip out ampersands right before non-whitespace characters, i.e.
+                            // those used to determine the alt key shortcut
+                            text: parent.Accessible.name.replace(/&(?=\S)/g, "")
                         }
                     }
                 }