Add empty line before list

mkdocs doesn't seem to like this list, and according to their docs, it should have an empty line prior to any list, so there it goes.

docs/rules.md

@@ -5,6 +5,7 @@
 Compose is built upon the idea of a [unidirectional data flow](https://developer.android.com/jetpack/compose/state#state-hoisting), which can be summarised as: data/state flows down, and events fire up. To implement that, Compose advocates for the pattern of [hoisting state](https://developer.android.com/jetpack/compose/state#state-hoisting) upwards, enabling the majority of your composable functions to be stateless. This has many benefits, including far easier testing.
 
 In practice, there are a few common things to look out for:
+
 - Do not pass ViewModels (or objects from DI) down.
 - Do not pass `State<Foo>` or `MutableState<Bar>` instances down.