Part of https://github.com/flutter/flutter/issues/133171.

Removes from `TestWindow`:
* `localeTestValue`
* `clearLocaleTestValue`
* `localesTestValue`
* `clearLocalesTestValue`
* `initialLifecycleStateTestValue`
* `alwaysUse24HourFormatTestValue`
* `clearAlwaysUse24HourTestValue`
* `brieflyShowPasswordTestValue`
* `defaultRouteNameTestValue`
* `clearDefaultRouteNameTestValue`
* `semanticsEnabledTestValue`
* `clearSemanticsEnabledTestValue`
* `accessibilityFeaturesTestValue`
* `clearAccessibilityFeaturesTestValue`

These properties have reached the end of their deprecation period.