feat: final style edit for testing

Author: Josh Moore

src/md/_index.md

@@ -9,7 +9,7 @@
     4. [Desktop applications](#desktop-apps)
     5. [Mobile applications](#mobile-apps)
     6. [Hardware](#hardware)
-4. **[Useful links, tools, and advice](#useful-links-tools-and-advice)**
+4. [Useful links, tools, and advice](#useful-links-tools-and-advice)
     1. [Resources](#resources)
     1. [Books](#books)
     1. [Blog posts](#blog-posts)