Restore Realtime SEO for Drupal (yoast_seo) to the SEO tools recipe

Over to Pam for final review.

How does this module work, does it connect to a this party or is all local? Asking for privacy compliance.

#6: Nope, I asked the Yoast maintainer that specific question in Slack and was told that the module uses no externally loaded JS. I installed it locally and confirmed that the JS library is locally available and not CDN-loaded. So this appears to be all clear from the privacy perspective.

I tested and found a few issues. The module's config form is still broken, which @phenaproxima has a fix for and will provide to the module.

I wasn't loving the theme input thing, the extra page with a continue button is super confusing. Looked into it with @phenaproxima and if we set the theme to NULL it uses the site's default theme, although this isn't reflected in the field widget settings. That can be fixed though.

So @phenaproxima has convinced me to approve this anyway and I will send all complaints about it his way!!!

Alright...with the caveat that we gotta fix Yoast's settings form, I have merged this into 1.x and cherry-picked to 1.0.x. Final feature for Drupal CMS 1.0.0!