Do not generate not-null assertion for argument of Collection.contains

Of course not only for contains but for other methods having INSTANCEOF bar.rier
Otherwise using platform null values becomes for such methods becomes
dangerous in cases like `platformString in setOf("", "")`

compiler/testData/codegen/boxWithJava/collections/platformValueContains/J.java

@@ -0,0 +1,7 @@
+import java.util.*;
+
+public class J {
+    public static String nullValue() {
+        return null;
+    }
+}