Fix typo in message

Author: lizmat

S03-operators/div.t

@@ -4,7 +4,7 @@ plan 6;
 
 isa_ok 10 div 0   , Failure, "10 div 0 softfails";
 isa_ok 10 / 0     , Rat, "10 / 0 is a Rat.";
-isa_ok 10 / 0.0   , Rat, "10 / 0.0 is a rat";
+isa_ok 10 / 0.0   , Rat, "10 / 0.0 is a Rat";
 isa_ok 10 / 0e0   , Failure, "10 / 0e0 softfails";
 isa_ok (1/1) / 0e0, Failure, "(1/1) / 0e0 softfails";
 isa_ok 1e0 / (0/1), Failure, "1e0 / (0/1) softfails";