Add an example to va-alert - Documentation

[caw310]

Description

This work stems from this Experimental Design [Alert with Secondary Link CTA].
Add or update documentation and guidance for va-alert on design.va.gov with an example using primary action link.
Add guidance to make it clear this use case is okay to use.

Tasks

• Write or update component documentation for design.va.gov
• Coordinate with accessibility specialist to create or update accessibility guidance
• Request documentation draft review
• Once documentation is approved, publish to design.va.gov

Acceptance Criteria

• Component documentation is published on design.va.gov

[caw310]

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