Disabling/Enabling Nav Link Proxies Causes UNavigationSystem::TestPathSync() to Always Return True

When using ANavLinkProxy::SetSmartLinkEnabled() to toggle a Smart Link, it will cause UNavigationTestPathSync() to always return true.

1. Open the attached project
2. PIE (Notice the TestPathSync() points are returning true and false correctly)
3. Press the D key to toggle SetSmartLinkEnabled()

Result: TestPathSync() calls are now all returning true.

Expected: The TestPathSync() results would be the same as before toggling the smart links.