Minor update to the book for nims 2.0 release as of today (01.08.2023)

[PhilippMDoerner]

This is honestly more of a notification than an actual issue.

I'm not sure if you're already aware that nim 2.0 was released today (https://nim-lang.org/blog/2023/08/01/nim-v20-released.html).

With that come some minor changes, but honestly it shouldn't be much given that I'm pretty impressed with how on top you've been with all developments. At least from what I can gather skimming through: https://ssalewski.de/nimprogramming.html. Seems to me like it'd mostly just be a slight wording change in the About this book section?