Add aria-label to inputs for container_registry

What does this MR do and why?

Adds aria-labels to the form inputs on the container_registry page.

References

Please include cross links to any resources that are relevant to this MR. This will give reviewers and future readers helpful context to give an efficient review of the changes introduced.

• https://gitlab.com/gitlab-org/gitlab/-/issues/511728
• https://gitlab.com/gitlab-org/gitlab/-/issues/511882

MR acceptance checklist

Please evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

Screenshots or screen recordings

No changes.

How to set up and validate locally

1. Apply diff:

diff --git a/app/controllers/projects/registry/application_controller.rb b/app/controllers/projects/registry/application_controller.rb
index 9a94de3859ae..aa9964bcc1ec 100644
--- a/app/controllers/projects/registry/application_controller.rb
+++ b/app/controllers/projects/registry/application_controller.rb
@@ -14,7 +14,7 @@ class ApplicationController < Projects::ApplicationController
       private
 
       def verify_registry_enabled!
-        render_404 unless Gitlab.config.registry.enabled
+        # render_404 unless Gitlab.config.registry.enabled
       end
     end
   end

1. Open http://127.0.0.1:3000/gitlab-org/gitlab-test/container_registry.

Related to #511728