KT-50033 Add missing public API packages to module-info and setup a test

The test checks that new packages are not accidentally non-exported,
so each new stdlib package must be either exported or specified in that
test's expected non-exported package list.

compiler/tests/org/jetbrains/kotlin/code/CodeConformanceTest.kt

@@ -46,6 +46,7 @@ class CodeConformanceTest : TestCase() {
                 "libraries/kotlin.test/js/it/node_modules",
                 "libraries/reflect/api/src/java9/java/kotlin/reflect/jvm/internal/impl",
                 "libraries/reflect/build",
+                "libraries/stdlib/jdk8/moduleTest/NonExportedPackagesTest.kt",
                 "libraries/stdlib/js-ir/.gradle",
                 "libraries/stdlib/js-ir/build",
                 "libraries/stdlib/js-ir-minimal-for-test/.gradle",