Add new failing test case for 048 (clause guards)

  It seems like we don't properly handle clause guards for wildcard
  patterns. Seems like a codegen issue here as the code type-check
  properly.

examples/acceptance_tests/048/lib/tests.ak

@@ -45,3 +45,25 @@ test foo_4() {
       False
   }
 }
+
+type Seasons {
+  Winter
+  Spring
+  Summer
+  Fall
+}
+
+fn is_cold(season, hour) {
+  when season is {
+    Winter | Fall ->
+      True
+    _ if hour >= 18 ->
+      True
+    _ ->
+      False
+  }
+}
+
+test foo_5() {
+  !is_cold(Spring, 15) && is_cold(Summer, 22)
+}

examples/acceptance_tests/048/validators/foo.ak

@@ -1,12 +1,12 @@
 fn when_tuple(a: (Int, Int)) -> Int {
   when a is {
-    (a, b) ->
+    (a, _b) ->
       a
   }
 }
 
 validator {
-  fn spend(a: Data, b: Data, c) -> Bool {
+  fn spend(a: Data, b: Data, _c) -> Bool {
     when_tuple((4, 1)) == 4
   }
 }