fix typo

Author: coke

doc/Language/signatures.rakudoc

@@ -1010,7 +1010,7 @@ Example with a positional parameter:
 =begin code
 my constant PositionalAt = Positional.new;
 
-sub a (@list = PositionalAt) { say @list === PositionalAt }  # here, one can also use =:=, the container indentity operator
+sub a (@list = PositionalAt) { say @list === PositionalAt }  # here, one can also use =:=, the container identity operator
 a;              # OUTPUT: «True␤»
 a [1, 2, 3];    # OUTPUT: «False␤»
 =end code