Issue #3269215 by slucero, dpi: EntityTypeInterface::getKey() is typehinted as...

Issue #3269215 by slucero, dpi: EntityTypeInterface::getKey() is typehinted as possibly returning bool, but never returns true

(cherry picked from commit 9e8f4c8e)

core/lib/Drupal/Core/Entity/EntityTypeInterface.php

@@ -107,7 +107,7 @@ public function getKeys();
    * @param string $key
    *   The name of the entity key to return.
    *
-   * @return string|bool
+   * @return string|false
    *   The entity key, or FALSE if it does not exist.
    *
    * @see self::getKeys()