Option to force RAM assignment to first step on PBS creation.

Description: Currently, when a user creates a PBS, they are automatically assigned to all workflow steps for which they appear in the workflow. An option is needed to create a new PBS to force the creator to be assigned only to the first step.

Use Case/Example: The same user may Author some BOEs and review other BOEs in the same proposal. This means they will be available to assign to both the author and review workflow steps. When they create the PBS, they are the author of that BOE and not a reviewer.