Adapt one test to fatalization of $#

t/op/heredoc.t

@@ -109,7 +109,7 @@ HEREDOC
 
     # [perl #125540] this asserted or crashed
     fresh_perl_like(
-	q(map d$#<<<<""),
+	q(map d<<<<""),
 	qr/Can't find string terminator "" anywhere before EOF at - line 1\./,
 	{},
 	"Don't assert parsing a here-doc if we hit EOF early"