Entity reference does not validate auto-created entities

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+  public function isValidationRunning() {
+    return $this->validationRunning;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function isValidated() {
+    return $this->validated;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setValidated($validated) {
+    $this->validated = $validated;
+    return $this;
   }

1. these functions should be typehinted

2. Will need a change record for the new functions on the interface (as they may be used by others)

Since this is adding a new error message tagging for usability review. Can bring up in the #ux channel in slack to bring up early.

Curious though if there's a good way to test this one?

The latest posted patch fails to apply on Drupal 10.2.x. It seems to just be a merge conflict on the tests though, so the underlying code should still be good.

Posting reroll for 10.2. I did not take the above suggestion re: typehinting into account as I was focused on just making a working patch.

However, I'm having trouble verifying that this still does what I thought it was supposed to do. I'm certain I originally applied this patch so that custom validators I implemented on taxonomy terms run when migrating content via CSV. This would ideally have two effects:

1. Nodes that try to create taxonomy terms with invalid names fail to import.
2. Taxonomy terms with invalid names are never created in the first place.

The first point always happens with or without the patch on both 10.1 and 10.2. The second point, however, does not -- the invalid taxonomy terms always get created and pollute the term list without getting referenced. Surely when I applied this patch it resolved one point or the other?... unfortunately I can't really revert the site back to 9.x to check.