Docs: fix typo in Accept header value
Docs: fix typo in Accept header value

This closes #250

Signed-off-by: Alexander Shorin <287dfd97d2274fe201ae7191a244ba25e475e13a@apache.org>

fkaempfer/couchdb,fkaempfer/couchdb,fkaempfer/couchdb,fkaempfer/couchdb,fkaempfer/couchdb,fkaempfer/couchdb