Add FeatureCard component

What does this MR do?

Add FeatureCard component

This new component represents a given feature for the redesigned Security & Compliance Configuration page.

Addresses #328385 (closed), part of &5820 (closed).

Designs: #326926 (closed)

Screenshots (strongly suggested)

These screenshots were created by hacking the existing Security Configuration page with mock data and mangling the template; see this very rough patch: poc-security-configuration-redesign.patch

The left column in each screenshot represents the cards as they should be shown for a non-Ultimate project, and the right column shows the cards as you might see them on an Ultimate project.

Finally, there's a screenshot for how they look in Dark Mode.

light	dark

Does this MR meet the acceptance criteria?

Conformity

• I have included a changelog entry, or it's not needed. (Does this MR need a changelog?)
  • No changelog necessary, as this is so far an unused component.
• 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.

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.

Related to #328385 (closed)