add tests for jps-plugin (Kotlin Javascript projects)

jps-plugin/testData/general/KotlinJavaScriptProjectWithDirectoryAsLibrary/src/test1.kt

@@ -0,0 +1,7 @@
+import library.sample.pairAdd
+
+fun foo() {
+    val p = Pair(10, 20)
+    val x = pairAdd(p)
+    println("x=$x")
+}