Link to documentation specified by the "tag" on any endpoint page with that tag

[mcilroyc]

in my openapi yaml file I have a tag 'foo' and then a bunch of endpoints that specify that tag. On the docs page for each endpoint, I think it would be nice to have a link to the Foo guide page (as defined by the externalDocs.url for the tag)

tags:
  - name: Foo
    description: Foo operations and whatnot
    externalDocs:
      description: More info about Foo
      url: https://docs.bar.com/docs/foo-guide

And then an endpoint like

/v2/bar/foo:
    get:
      description: Returns foo sorted by foo-ness
      summary: Foo by foo
      tags:
        - Foo