[Feature]: Add Role based access control to running workflows - update task drown endpoint

[wouter1975]

Refinement of ticket after discussion on 11-2:

Requirements:

• Ability to assign privileges per group
• Ability to check privileges halfway a workflow
• Make it possible to check authorization at each input type step
  like suspend, callback input steps (iow when a user/proces changes the workflow into running state)
• Dropped requirement: ability to change the minimal rights in the UI. This should be a handled by the auth implementation of the application

Suggested solution

• Extend the graphql calls for populating the Tasks dropdown menu items, to include a state flag (eg isAllowed bool) to rendering the workflow item in normal or disabled state.

    "data": {
        "workflows": {
            "page": [
                {
                    "name": "task_clean_up_tasks",
                    "description": "Clean up old tasks",
                    "isAllowed": "true" ------------------> add this attribute
                },
                {
                    "name": "task_resume_workflows",
                    "description": "Resume all workflows that are stuck on tasks with the status 'waiting'"
                    "isAllowed": "false" ------------------> add this attribute
                },

In other tickets:

• Extend the stepdecorator to call an optional function, which is performing the isAllowed function by the attribute workflow_name, workflow_step_name (optional) and user. If this function returns true the workflow (step) can be executed.

  • Update the https://github.com/update, @inputstep and @workflow decorators to include the isAllowed function.
    [Feature]: Add Role based access control to running workflows - update decorators #782

• Extend the graphql calls for populating the Start dropdown menu items, to include a state flag (eg isAllowed bool) to rendering the workflow item in normal or disabled state.
  [Feature]: Add Role based access control to running workflows - update StartOptions endpoint #821