Migrate member lock checkbox to gitlab_ui_checkbox_component

What does this MR do?

Related to #336701 (closed)

This migrates the GitLab UI checkbox in ee/app/views/groups/_member_lock_setting.html.haml to gitlab_ui_checkbox_component.

Steps to test

1. Go to a group
2. Go to Settings > General
3. Expand the Permissions, LFS, 2FA section
4. See the checkbox in the Member lock sub-section

Screenshots

Before	After

Does this MR meet the acceptance criteria?

Conformity

• I have included changelog trailers, or none are needed. (Does this MR need a changelog?)
• I have added/updated documentation, or it's not needed. (Is documentation required?)
• I have properly separated EE content from FOSS, or this MR is FOSS only. (Where should EE code go?)
• I have added information for database reviewers in the MR description, or it's not needed. (Does this MR have database related changes?)
• I have self-reviewed this MR per code review guidelines.
• This MR does not harm performance, or I have asked a reviewer to help assess the performance impact. (Merge request performance guidelines)
• I have followed the style guides.
• This change is backwards compatible across updates, or this does not apply.

Availability and Testing

• I have added/updated tests following the Testing Guide, or it's not needed. (Consider all test levels. See the Test Planning Process.)
• I have tested this MR in all supported browsers, or it's not needed.
• I have informed the Infrastructure department of a default or new setting change per definition of done, or it's not needed.