add expect false test

examples/acceptance_tests/076/lib/tests.ak

@@ -1,14 +1,11 @@
 test expect_positive() {
-  let val =
-    5
-  expect True =
-    val > 0
+  let val = 5
+  expect True = val > 0
+  True
+}
+
+test expect_false() {
+  let val = 5
+  expect False = val < 0
   True
 }
-// test expect_fail() {
-//   let val =
-//     5
-//   expect True =
-//     val < 0
-//   True
-// }