Make sure new nav works well with the donate banner

[mmmavis]

Make sure new nav shows up properly when donate banner is enabled on the site.

Link to sample test page: https://foundation-s-tp1-1191-d-dz53nx.herokuapp.com/en/
Related PRs/issues: #

To test

Desktop

1. View https://foundation-s-tp1-1191-d-dz53nx.herokuapp.com/en/ on a desktop screen size
2. Hover over the new nav
3. Make sure the dropdown appear below the nav bar like the screenshot below

Mobile

1. View https://foundation-s-tp1-1191-d-dz53nx.herokuapp.com/en/ on a mobile screen size
2. Toggle on the new nav by clicking the hamburger icon
3. Make sure the nav takes over the entire screen like the screenshot below

┆Issue is synchronized with this Jira Story