UUID is regenerated every time a pattern is saved

Added change to \Drupal\pathauto\Entity\PathautoPattern::addSelectionCondition() which persists the UUID if the configuration includes a uuid property saving the need to regenerate a unique UUID everytime.

This looks good at first glance, but it's a non-trivial amount of code to the form handling, would be great to make sure we have tests covering this. There is \Drupal\Tests\pathauto\FunctionalJavascript\PathautoUiTest::testPatternsWorkflow, where we add, edit and delete patterns, but we have little coverage for the conditions, specifically nothing about removing them.

So, would be good to extend that by removing the bundle condition and then also once save a pattern and ensure nothing on the config entity changes (load config entity, toArray(), save in UI without changes, then load again and compare)