Small documentation tweaks

doc/src/manual/cowboy_req.stream_trailers.asciidoc

@@ -67,4 +67,4 @@ cowboy_req:stream_trailers(#{
 
 link:man:cowboy_req(3)[cowboy_req(3)],
 link:man:cowboy_req:stream_reply(3)[cowboy_req:stream_reply(3)],
-link:man:cowboy_req:stream_reply(3)[cowboy_req:stream_body(3)]
+link:man:cowboy_req:stream_body(3)[cowboy_req:stream_body(3)]

doc/src/manual/cowboy_stream.asciidoc

@@ -411,6 +411,7 @@ tuple.
 
 == Changelog
 
+* *2.2*: The trailers command was introduced.
 * *2.0*: Module introduced.
 
 == See also