Issue/404

[TheDanMiller]

Updates 404 page

Summary

Updated default USWDS 40 to match Figma mockup

Type of change

• [x] New feature (non-breaking change which adds functionality)

How To Test

1. Navigate to a route that does not exist
2. See the new 404 page

Checklist:

• [x] My code follows the style guidelines of this project and has no linting errors
• [x] I have performed a self-review of my code
• [x] I have commented my code, particularly in hard-to-understand areas
• [x] I have made corresponding changes to the documentation, including any applicable ADRs
• [x] My changes generate no new warnings
• [x] I have added tests that fail without these changes
• [x] New and existing tests (unit, integration, accessibility) pass locally
• [x] Documentation updated
• [x] If there are security concerns they are addressed or ticketed after being discussed

[codeclimate[bot]]

Code Climate has analyzed commit 25392b84 and detected 0 issues on this pull request.

The test coverage on the diff in this pull request is 100.0% (80% is the threshold).

This pull request will bring the total coverage in the repository to 95.4%.

View more on Code Climate.