Issue #3437023: Copy RequestedUpdateValidator to automatic_updates_extensions

...ates_extensions/automatic_updates_extensions.services.yml

...tes_extensions/src/Validator/RequestedUpdateValidator.php

.../tests/src/Functional/StatusCheckerRunAfterUpdateTest.php

..._extensions/tests/src/Functional/SuccessfulUpdateTest.php

...xtensions/tests/src/Functional/UnsuccessfulUpdateTest.php

...dates_extensions/tests/src/Functional/UpdateErrorTest.php

...s/src/Kernel/AutomaticUpdatesExtensionsKernelTestBase.php

...sts/src/Kernel/Validator/RequestedUpdateValidatorTest.php

...tests/src/Kernel/Validator/UpdateReleaseValidatorTest.php