book: update nl

Updated via the `update-book.yml` GitHub workflow.

Author: ttaylorr

external/book/content/book/nl/v2/_index.html

@@ -8,7 +8,7 @@
   language_code: nl
   front_page: true
   repository_url: https://github.com/progit/progit2-nl
-  sha: 57bf9abf9d41a2c4962ee3ce674da65bb182b349
+  sha: f939f23b0f79f8fadf4b7f19a2ef734279f440af
 page_title: Git - Book
 url: "/book/nl/v2.html"
 aliases:

external/book/sync/book-nl.sha

@@ -1 +1 @@
-57bf9abf9d41a2c4962ee3ce674da65bb182b349
+f939f23b0f79f8fadf4b7f19a2ef734279f440af