fix open C<>

Author: gfldex

doc/Language/typesystem.pod6

@@ -305,7 +305,7 @@ TODO
 
 =head3 Versioning and Authorship
 
-Versioning and authorship can be applied via adverbs C«:ver<>» and C«:auth<>.
+Versioning and authorship can be applied via adverbs C«:ver<>» and C«:auth<>».
 Both take a string as argument, for C<:ver> the string is converted to a
 L<Version|/type/Version> object. To query a grammars version and author use
 C<.^ver> and C<^.auth>.