docs: adding a comment

site/scripts/get-contributors.js

@@ -42,6 +42,7 @@ async function main() {
 	}
 
 	await sprite.quality(80).write(`../static/contributors.jpg`);
+	console.log('remember to additionally optimize the resulting /static/contributors.jpg image file via e.g. https://squoosh.app ');
 
 	const str = `[\n\t${authors.map(a => `'${a.login}'`).join(',\n\t')}\n]`;