Update background color of 2ndary nav

[sterkenburgsara]

Description

Currently, the background color of the secondary navigation bar in production/staging is the same exact hex code shade of blue as the hover-state of the mega-menu. We should have some visual distinction between the two since they butt up against one another directly.

User story

As a Cartography team member, I want to update the background color of the secondary nav to match what is in Figma, so that it is distinct from the hover state of the primary mega menu on VA.gov (desktop).

Notes

• On screens larger than mobile, the mega menu is triggered by selecting dropdown components. When hovering over them, the dropdowns are the exact same shade of blue as the background of the secondary navigation component.
• We intentionally specified a different shade of blue to avoid this, it is specified in the Figma file here
• Relevant Slack thread here

Possible tasks:

• [ ] Update the background color of secondary navigation bar:
  • Current: #005EA2
  • Color we want it to be: #0071BB
• [ ] Check design system color vars

Acceptance criteria

• [x] Background color of secondary nav is now correct (#0071BB)
• [ ] UX review
• [ ] QA review
• [ ] A11y review

[wesrowe]

@nichia this shows as "ready" on the board, but don't you have a PR up for it?