How to deal with PipeModel Tandem.REQUIRED option?

[samreid]

In #78 @marlitas and I observed this review comment:

  public constructor( providedOptions?: PipeModelOptions ) {
    const options = optionize<PipeModelOptions, SelfOptions, PhetioObjectOptions>()( {
      isOpen: false,
      phetioType: PipeModel.PipeModelIO,
      //REVIEW replace with PickRequired<PhetioObjectOptions, 'tandem'>
      tandem: Tandem.REQUIRED,
      phetioDynamicElement: true
    }, providedOptions );

This issue requires further discussion, so we are promoting that REVIEW comment to this issue.

We would like to add PickRequired<PhetioObjectOptions, 'tandem'> to the options, but we don't want to remove tandem: Tandem.REQUIRED until phetsims/tandem#253 has been completed.

[marlitas]

phetsims/tandem#253 has been closed, and this issue has been dealt with accordingly, by removing Tandem.REQUIRED and replacing with a PickRequired. Closing.