Fix Cloudflare caching for inter.css

[manuelmeurer]

Firstly, thanks for this great font and your continued work on it! 👏

Describe the bug

I am using the CDN to load the font and noticed that the caching for inter.css could be improved.
Cloudflare reports a cache miss on every load.
(the subsequent request to https://rsms.me/inter/font-files/InterVariable.woff2?v=4.1 shows a cache hit.)

https://developers.cloudflare.com/cache/concepts/cache-responses/

There could be several reasons for this, it's hard to diagnose without knowing the setup.

To Reproduce
Steps to reproduce the behavior:

1. Add https://rsms.me/inter/inter.css to your website
2. Open the Chrome dev tools and load the page
3. Check the response headers for the request to inter.css

Expected behavior
A cache hit (cf-cache-status = HIT)

Screenshots

Environment

• OS: macOS Tahoe
• App that renders the font: Latest Chrome
• Version of font: 4.1