Fix incorrect and unneeded link to self

Author: stoned

doc/Type/IO/CatHandle.pod6

@@ -8,7 +8,7 @@
 
 This class has been available in Rakudo since version 2017.06.
 
-The C<IO::CatHandle|/type/IO::CatHandle> class provides a means to create an L<IO::Handle|/type/IO::Handle> that
+The C<IO::CatHandle> class provides a means to create an L<IO::Handle|/type/IO::Handle> that
 seamlessly gathers input from multiple L<IO::Handle|/type/IO::Handle> and L<IO::Pipe|/type/IO::Pipe> sources.
 
 All of the L<IO::Handle|/type/IO::Handle>'s methods are implemented, and while attempt to use