UBlueprintNodeSpawner::ClearCachedTemplateNode

Removes the spawner's cached template node (if it has one), meaning that the next [GetTemplateNode()](API\Editor\BlueprintGraph\UBlueprintNodeSpawner\GetTemplateNode) call will spawn a new one (and that calls to [GetCachedTemplateNode()](API\Editor\BlueprintGraph\UBlueprintNodeSpawner\GetCachedTemplateNode) will return null).