add bullet list to clue tutorial links

Author: FoamyGuy

_board/clue_nrf52840_express.md

@@ -27,8 +27,8 @@ After designing it, the board was close enough to micro:bit-shape-size that we m
 
 ## Tutorials
 
-[CLUE Overview](https://learn.adafruit.com/adafruit-clue)
-[Projects and Guides](https://learn.adafruit.com/products/4500/guides)
+* [CLUE Overview](https://learn.adafruit.com/adafruit-clue)
+* [Projects and Guides](https://learn.adafruit.com/products/4500/guides)
 
 ## Purchase
 * [Adafruit CLUE](https://www.adafruit.com/product/4500)