/pod is a special endpoint.  It's not a wrapper around an Search::Elasticsearch type,
so it doesn't return JSON.  For this reason we cannot hit this endpoint via
Search::Elasticsearch.pm.

The default content type is HTML, as created via Pod::Simple::XHTML.  Available
content types are:

text/plain
text/x-pod
text/x-markdown
text/html

See lib/MetaCPAN/Server/View/Pod.pm in the cpan-api repo for more information.