Update pull_request_template.md

pull_request_template.md

@@ -35,6 +35,7 @@
 	- Has a Table of Contents section.
 		- Should be named `Contents`, not `Table of Contents`.
 		- Should be the first section in the list.
+		- Should only have one level of sub-lists, preferably none.
 	- Has an [appropriate license](https://github.com/sindresorhus/awesome/blob/master/awesome.md#choose-an-appropriate-license).
 		- That means something like CC0, **not a code licence like MIT, BSD, Apache, etc.**
 		- If you use a license badge, it should be SVG, not PNG.