add review snippets to testimonials page

[DTrejo]

https://developers.google.com/search/docs/data-types/review-snippet

<script type="application/ld+json">
{
  "@context": "http://schema.org/",
  "@type": "website",
  "name": "David Trejo",
  "description": "\"My favorite tech lead, ever.\"",
  "aggregateRating": {
    "@type": "AggregateRating",
    "ratingValue": "5",
    "bestRating": "5",
    "ratingCount": "20"
  }
}
</script>

details on getting it to actually work: https://whitespark.ca/blog/how-to-use-aggregate-review-schema-to-get-stars-in-the-serps/

and maybe add article markup to articles, maybe
https://developers.google.com/search/docs/data-types/article#non-amp