Adds form to add container tag protection rules

What does this MR do and why?

Adds form to add container tag protection rules

The form is implemented within a Drawer component.

Note: Form submission will be implemented as a follow-up MR

References

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• Design: https://gitlab.com/gitlab-org/gitlab/-/issues/499871/designs/protected-container-tags.png

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After	Drawer opened

How to set up and validate locally

1. Setup container registry.

2. Enable feature flag

   Feature.enable(:container_registry_protected_tags)

3. Visit Project > Settings > Packages and registries.

4. Expand Container registry section

5. Under Protected container tags section, confirm that a button Add protection rules exists

6. Confirm that Clicking on the button opens a Drawer with a form to add protection rules.

Submit behaviour of the form will be added in a follow-up MR.

Related to #499871