fix: #3621846 Flag the input-checkbox and input-submit SDCs noUi so Canvas does not offer theme-internal atoms as components

Issue: https://www.drupal.org/project/vartheme_bs5_horizonaid/issues/3621846

Adds noUi: true to components/atoms/input-checkbox/input-checkbox.component.yml and components/atoms/input-submit/input-submit.component.yml, in the same position every other theme-internal atom uses.

Both are pure Bootstrap form-input wrappers whose entire prop set is *_utility_classes, children and attributes. Without the flag, Drupal\canvas\Plugin\Canvas\ComponentSource\SingleDirectoryComponentDiscovery::discover() keeps them, so Canvas creates enabled Component config entities for them on the next cache rebuild and offers them in the component library. Their siblings — details, fieldset, form-element, radios, select — are all already flagged.

Verified on a clean Drupal CMS 2.1.4 + Horizon Aid build: after the change Canvas ignores both, and the Horizon Aid recipe no longer has to create and disable them (drupal.org/project/horizonaid/issues/3621847).

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