Make "clone on publish" compatible with entity_workflow module

Created a MR. Please review.

Reviewed.

Thinking more about this, I think the issue should be moved to the entity_workflow module, and implemented like this in the entity_workflow_workspace submodule:

- implement a hook_form_alter that covers both entity_workflow_form and entity_workflow_simple_transition_form
- in that form alter, build and render the workspace publish form (directly for entity_workflow_simple_transition_form, using #states for entity_workflow_form)
- ensure that all form validators of the workspace publish form will run
- ensure that \Drupal\workspaces\Form\WorkspacePublishForm::submitForm() does not run (because the actual publishing will be done by the workflow transition)

This way, every customization/alter of the workspace publish form should be available in the workflow transition form.

@amateescu - Thank you! Moving this to the entity_workflow module.

ajits → closed merge request !101

> implement a hook_form_alter that covers both entity_workflow_form and entity_workflow_simple_transition_form

Done

> in that form alter, build and render the workspace publish form (directly for entity_workflow_simple_transition_form, using #states for entity_workflow_form)

This was not possible because the EntityWorkflowSimpleTransitionForm form uses routeMatch to check for the workspace transition; and the transition is not available (on load) for EntityWorkflowForm.

I have checked for other details and the MR should cover it. Please review.