Use Class.forName instead of ClassLoader.loadClass in reflection

This fixes an issue in constructing annotation instances with array
class elements. For some reason, behavior of `ClassLoader.loadClass`
differs from `Class.forName` in handling arrays, namely:

* `loadClass("[Ltest.Foo;")` returns null
* `Class.forName("[Ltest.Foo;")` returns class for array of test.Foo

Overall, there doesn't seem to be any way to load an array class with
`CLassLoader.loadClass`.

We pass initialize=false to forName because this is the behavior of
ClassLoader.loadClass: it doesn't perform class initialization (e.g.
<clinit> is not executed).

 #KT-31318 Fixed

compiler/tests/org/jetbrains/kotlin/codegen/BlackBoxCodegenTestGenerated.java

@@ -20083,6 +20083,11 @@ public class BlackBoxCodegenTestGenerated extends AbstractBlackBoxCodegenTest {
                     KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("compiler/testData/codegen/box/reflection/annotations/onTypes"), Pattern.compile("^(.+)\\.kt$"), TargetBackend.JVM, true);
                 }
 
+                @TestMetadata("arrayKClass.kt")
+                public void testArrayKClass() throws Exception {
+                    runTest("compiler/testData/codegen/box/reflection/annotations/onTypes/arrayKClass.kt");
+                }
+
                 @TestMetadata("classLiteralWithExpectedType.kt")
                 public void testClassLiteralWithExpectedType() throws Exception {
                     runTest("compiler/testData/codegen/box/reflection/annotations/onTypes/classLiteralWithExpectedType.kt");