markdownlint: fix md004 (#175)

* markdownlint: fix md004

* use `-` for lists

Co-authored-by: simonsan <14062932+simonsan@users.noreply.github.com>

.markdownlint.yaml

@@ -1,5 +1,4 @@
 ---
-MD004: false
 MD010:
   code_blocks: false
 MD013:

patterns/newtype.md

@@ -86,9 +86,9 @@ the wrapper type.
 Newtypes are very common in Rust code. Abstraction or representing units are the
 most common uses, but they can be used for other reasons:
 
-* restricting functionality (reduce the functions exposed or traits implemented),
-* making a type with copy semantics have move semantics,
-* abstraction by providing a more concrete type and thus hiding internal types, e.g.,
+- restricting functionality (reduce the functions exposed or traits implemented),
+- making a type with copy semantics have move semantics,
+- abstraction by providing a more concrete type and thus hiding internal types, e.g.,
 
 ```rust,ignore
 pub struct Foo(Bar<T1, T2>);