Update link for named-parameter aliases in signatures documentation

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Author: arkiuat

doc/Language/signatures.rakudoc

@@ -964,7 +964,7 @@ argument or not. C<:$colour> will not only be the name of the aliased variable,
 but also a new named argument (used in the second invocation). However,
 C<$kind> will just be the name of the aliased variable, that does not create a
 new named argument. More uses of aliases can be found in
-L<sub MAIN|/language/create-cli#sub_MAIN>.
+L<sub MAIN|/language/create-cli#Aliases_for_named_parameters>.
 
 A function with named arguments can be called dynamically, dereferencing a
 L<C<Pair>|/type/Pair> with C<|> to turn it into a named argument.