message: fix: on destroy remove the lastBootstrappedModule
  If exit event was triggered twice we would try to destroy an already
  destroy module ref.
diff: @@ -260,6 +260,8 @@ export class NativeScriptPlatformRef extends PlatformRef {
  "nativescript-angular/platform-common.exitCallback", () => {
  const lastModuleRef = lastBootstrappedModule ? lastBootstrappedModule.get() : null;
  if (lastModuleRef) {
  + lastBootstrappedModule = null;
  +
  lastModuleRef.destroy();
  }
  