Switch to new fonts

What does this MR do and why?

It adds the new fonts to the project. Font definitions as well as fonts preload is done conditionally - behind the FF new_fonts or when the URL has a query parameter new_fonts. So to see the new fonts in action either

Option 1

Enable the feature flag. Thus every page will have the new fonts applied.

rails c
Feature.enable(:new_fonts)

Option 2

Add the query parameter to the URL if you'd like to check the specific page with new fonts

e.g. Open one page with query parameter added and another without and compare them.

📓 It is not that obvious when new fonts are applied. In Chrome you can check dev tools, inspect the element and in the computed styles tab at the very bottom you'll see the Rendered Fonts.

Screenshots or screen recordings

Related to #377737 (closed)