Node Revision Support

Problem/Motivation

When a user goes to update their submitted webform, using the mappings we can already get the node to update along with the submission. But, if revisions are enabled on the node, no new revision is created. I have created my own patch that just sets the revision status to TRUE on update, but it would be nice to be able to have a setting on each WCC instance to allow for revisions to be saved if revisions are enabled on the node.

Steps to reproduce

1. Submit Webform
2. Have user edit the webform
3. Re-submit the form
4. Check the node revisions, it just updates the latest revision and does not save a new one

Proposed resolution

Check the node to see if revisions are enabled, if so add code to add the revision. Ex:

// Save content.
try {
  $content->setNewRevision(TRUE);
  $content->setRevisionUserId(\Drupal::currentUser()->id());
  $result = $content->save();
}