typecheck: validate CALL object method args

tests/typecheck_method_call_bad.claro

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+CLASS Player
+    HAS score NUMBER
+
+    TEACH add points
+        CHECK TYPE points IS NUMBER
+        SET score score + points
+    END
+END
+
+NEW Player player
+CALL player.add WITH "five"

tests/typecheck_method_call_good.claro

@@ -0,0 +1,11 @@
+CLASS Player
+    HAS score NUMBER
+
+    TEACH add points
+        CHECK TYPE points IS NUMBER
+        SET score score + points
+    END
+END
+
+NEW Player player
+CALL player.add WITH 5