fix(nim): swap nimfmt with nimpretty

Nim 2.x+ comes with its own formatter (nimpretty).

Close: #7578
Co-authored-by: pietrangelo <pietrangelo@users.noreply.github.com>

modules/lang/nim/README.org

@@ -52,8 +52,8 @@ Alternatively, nim is usually available through your OS's package manager:
 - openSUSE: ~$ zypper install nim~
 
 ** Formatter
-
-Formatting is handled using the [[doom-module::editor format]] module via [[https://github.com/FedericoCeratto/nimfmt#installation][nimfmt]].
+Formatting is handled using the [[doom-module::editor format]] module via nimpretty
+(included with Nim).
 
 * TODO Usage
 #+begin_quote