Picks a coding client hasn't specified it can handle

[dkarvik]

Given these opts:

{:juxt.http/variants ({:juxt.http/content-type nil,                                                                                                                                             
                       :juxt.http/content-language (),                                                                                                                                          
                       :juxt.http/content-encoding ({:juxt.http/content-coding "deflate"})}),                                                                                                
 :juxt.http/request-headers {"accept-encoding" ({:juxt.http/codings "gzip"} {:juxt.http/codings "compress"}), "accept" nil, "accept-language" nil}}

pick produces a variant, but the client hasn't expressed that it can handle a content encoding of deflate.