Add more complex negative operator test

src/test/contracts/arithmetic.mligo

@@ -3,4 +3,9 @@
 let neg_op (n : int) : int =
   -n
 
+let foo (n : int) : int = n + 10
+
+let neg_op_2 (b: int) : int = -(foo b)
+
+
 

src/test/integration_tests.ml

@@ -184,6 +184,7 @@ let arithmetic_mligo () : unit result =
     let aux (name , f) = expect_eq_n_int program name f in
     bind_map_list aux [
       ("neg_op", fun n -> (-n)) ;
+      ("neg_op_2", fun n -> -(n + 10)) ;
     ] in
   ok ()