Remove Default Content module.

automated_testing_kit.info.yml

 name: 'Automated Testing Kit'
 type: module
-description: 'Provides functions useful for automated testing.'
+description: 'Provides tests and functions useful for automated testing.'
 core_version_requirement: ^9 || ^10
 package: 'Automated Testing Kit'
 version: 1.2
-dependencies:
-  - drupal:default_content
-
-default_content:
-  node:
-    - 78b457c5-e0a0-4a9e-b7b6-6fb3a7ed2a7c