https://www.greatfrontend.com/questions/javascript/html-serializer
Given an object which resembles a DOM tree, implement a function that serializes the object into a formatted string with proper indentation (one tab per nesting level) and one tag per line.
const tree = {
tag: 'body',
children: [
{ tag: 'div', children: [{ tag: 'span', children: ['foo', 'bar'] }] },
{ tag: 'div', children: ['baz'] },
],
};
serializeNode(tree);
// Output:
`<body>
<div>
<span>
foo
bar
</span>
</div>
<div>
baz
</div>
</body>`;
