NoArg: Fix IllegalAccessError on instantiating sealed class child via Java reflection (KT-18245)

plugins/noarg/noarg-cli/testData/box/kt18245.kt

@@ -0,0 +1,22 @@
+// WITH_RUNTIME
+
+annotation class NoArg
+
+sealed class Test {
+    abstract val test: String
+
+    @NoArg
+    data class Test1(override val test: String) : Test()
+
+    @NoArg
+    data class Test2(override val test: String) : Test()
+}
+
+fun box(): String {
+    Test::class.java.declaredConstructors.forEach { it.isAccessible = true }
+    Test.Test1::class.java.declaredConstructors.forEach { it.isAccessible = true }
+
+    val instance = Test.Test1::class.java.newInstance() // Error
+
+    return "OK"
+}