doc: update examples to use class syntax for Foo and Bar

Author: miguelmarcondesf

doc/api/assert.md

@@ -272,9 +272,17 @@ strictEqual({ a: 1 }, { b: { c: 1 } });
 The `skipPrototypeComparison` option affects all deep equality methods:
 
 ```js
-function Foo(a) { this.a = a; }
+class Foo {
+  constructor(a) {
+    this.a = a;
+  }
+}
 
-function Bar(a) { this.a = a; }
+class Bar {
+  constructor(a) {
+    this.a = a;
+  }
+}
 
 const foo = new Foo(1);
 const bar = new Bar(1);

doc/api/util.md

@@ -1581,9 +1581,17 @@ enumerable properties are deeply strictly equal.
 ```js
 const util = require('node:util');
 
-function Foo(a) { this.a = a; }
+class Foo {
+  constructor(a) {
+    this.a = a;
+  }
+}
 
-function Bar(a) { this.a = a; }
+class Bar {
+  constructor(a) {
+    this.a = a;
+  }
+}
 
 const foo = new Foo(1);
 const bar = new Bar(1);