About Notify - Contact content added

[heyitsmebev]

As part of the new About Notify content section, this PR is the implementation for "Security"

Definition of Done

• Should include a side navigation
• Should be able to easily navigate to About Notify content
• Should meet a11y standards

Figma: https://www.figma.com/proto/aAWhlPzOP6kfVFnCCAfSZZ/notify.gov?page-id=2339%3A3817&node-id=5392-875&node-type=frame&viewport=2870%2C-701%2C0.48&t=nfkxOXnOCIFQB1yK-1&scaling=min-zoom&content-scaling=fixed&starting-point-node-id=5392%3A875

Content: https://docs.google.com/document/d/1lP8I0Jxu0B26cmTGBQcoHCbfSvKKHQBE6gzTL9HUheE/edit?tab=t.0#heading=h.icyigvoln8tg

[dmvancura]

take a look at the About Notify Contact page copy doc, as Cathy and I made updates as of this morning at 10amET @heyitsmebev. for example, "notify is designed to be easy to move" is deleted from the copy doc

[jonathanbobel]

@heyitsmebev this will be moved out of the /about URL and side navigation into it's own top-level navigation, along with the Join Notify content