Update type links

Author: coke

doc/Language/concurrency.rakudoc

@@ -831,14 +831,14 @@ the critical section the code should be as quick as possible.
 =head2 Lock::Async
 
 L<C<Lock::Async>|/type/Lock::Async> is a mutual exclusion mechanism much like
-Lock, but it exposes its functionality through C<Promise>s, allowing the use of
+Lock, but it exposes its functionality through L<C<Promise>|/type/Promise>s, allowing the use of
 C<await> when waiting for a lock to become available, instead of blocking an
 entire thread.
 
 Another difference is that it is not re-entrant, meaning that the lock is not
 considered available to code that is C<protect>ed by the lock.
 
-C<Lock::Async> is more high-level than C<Lock>, but it is still considered a
+L<C<Lock::Async>|/type/Lock::Async> is more high-level than L<C<Lock>|/type/Lock>, but it is still considered a
 low-level primitive. Higher-level primitives should be preferred over mutating
 shared data inside critical sections.