Remove unused NLS entry

Author: HeikoKlare

bundles/org.eclipse.ui.workbench/eclipseui/org/eclipse/ui/internal/messages.properties

@@ -502,7 +502,6 @@ ThemeChangeWarningText = Restart for the theme changes to take full effect
 ThemeChangeWarningTitle = Theme Changed
 RescaleAtRuntimeSettingChangeWarningTitle = DPI Setting Changed
 RescaleAtRuntimeSettingChangeWarningText = Restart for the DPI setting changes to take effect
-HiDpiSettingsGroupTitle = HiDPI settings
 RescaleAtRuntimeDescription = Activating this option will dynamically scale all windows according to the monitor they are currently in
 RescaleAtRuntimeEnabled = Use monitor-specific UI &scaling
 # --- Workbench -----