Link rel=service-desc advertises openapi+json, but resource returns a yaml file with content-type text/plain

[philvarner]

Describe the bug

Franklin advertises the service-desc link as application/vnd.oai.openapi+json;version=3.0, but actually delivers an OpenAPI YAML file.

Code is:

franklin/application/src/main/scala/com/azavea/franklin/api/services/LandingPageService.scala

Line 37 in 0cb5d28

Link(

Link in Landing Page:

    {
      "href": "https://example.org/open-api/spec.yaml",
      "rel": "service-desc",
      "type": "application/vnd.oai.openapi+json;version=3.0",
      "title": "Open API 3 Documentation"
    },

Expected behavior

Link has type application/vnd.oai.openapi;version=3.0 (note without the +json) and retrieving that delivers a OpenAPI JSON file with Content-Type header "application/vnd.oai.openapi;version=3.0".

Additional context

The content type returned by SwaggerHttp4s (in a library) is incorrect, but this component is deprecated anyway in favor of
this newer OpenApi component for tapir https://github.com/softwaremill/tapir/tree/master/docs/openapi-docs/src/main/scala/sttp/tapir/docs/openapi