Fix overhang on mobile in 0.14.0 release notes

[mtlynch]

Congrats on the latest release!

I tried reading the release announcement on a Pixel 7a, and the rendering leaves a lot of whitespace due to one long hash:

I believe these CSS changes should fix the overhang.

I am not able to verify that this fix fixes the issue, as I'm not able to get the release notes to render at all when I run zig build serve locally. I can get most of the site to serve, but on my dev system, hardcodes the release notes to https://ziglang.org/download/0.14.0/release-notes.html rather than the http://127.0.0.1:1990 domain.

If I manually replace the domain and construct a URL as http://127.0.0.1:1990/download/0.14.0/release-notes.html, I get a 404 even though other pages work.