Fix closing details tag (#2116)

qwandor · web-flow · commit 5f72514f042e · 2024-06-03T10:54:40.000-04:00
diff --git a/src/methods-and-traits/traits/supertraits.md b/src/methods-and-traits/traits/supertraits.md
@@ -38,4 +38,4 @@ This is sometimes called "trait inheritance" but students should not expect this
 to behave like OO inheritance. It just specifies an additional requirement on
 implementations of a trait.
 
-<details>
+</details>
