Enable client to check the latest version instead of the stable version (Recommendation Setting)

This is an old policy for auto update. It is now recommended to use the new AU2 series policies. Default policy is disabled. This policy depends on EnableClientAutoUpdate, if EnableClientAutoUpdate is disabled, AlwaysCheckLatestVersion will not work, even if it is enabled. (For msi package, EnableClientAutoUpdate is disabled by default. For exe, it is enabled) If EnableSilentAutoUpdate is enabled(default is enabled), it's better to use SetUpdatingChannel instead of this policy. If this policy is enabled, client will check the latest version in the background. If this policy is disabled, client will check the stable version in the background. If this policy is not set, client will use the default setting.