Add codegen tests for old behavior of null checks

#KT-22275

compiler/testData/codegen/box/nullCheckOptimization/javaNullCheckThrowsNpe.kt

@@ -0,0 +1,22 @@
+// IGNORE_BACKEND_FIR: JVM_IR
+// TARGET_BACKEND: JVM
+// FILE: A.java
+
+import org.jetbrains.annotations.NotNull;
+
+public class A {
+    @NotNull
+    public static String foo() { return null; }
+}
+
+// FILE: test.kt
+
+fun box(): String {
+    try {
+        val s: String = A.foo()
+        return "Fail: NPE should have been thrown"
+    } catch (e: Throwable) {
+        if (e::class != NullPointerException::class) return "Fail: exception class should be NPE: ${e::class}"
+        return "OK"
+    }
+}