docs: fix examples being under wrong header

Author: RebeccaStevens

docs/rules/prefer-immutable-types.md

@@ -404,10 +404,6 @@ callback's parameters is undesirable.
 
 `false` by default.
 
-### `ignoreClasses`
-
-A boolean to specify if checking classes should be ignored. `false` by default.
-
 #### ❌ Incorrect
 
 <!-- eslint-skip -->
@@ -460,6 +456,10 @@ export const acceptsCallback: AcceptsCallback;
 
 </details>
 
+### `ignoreClasses`
+
+A boolean to specify if checking classes should be ignored. `false` by default.
+
 ### `parameters.*`, `returnTypes.*`, `variables.*`
 
 Override the options specifically for the given type of types.