add test for resolving links to library classes from KDoc comments

idea/testData/kdoc/navigate/jdkClass.kt

@@ -0,0 +1,4 @@
+import java.util.*
+
+fun fo<caret>o() {
+}

idea/testData/kdoc/navigate/stdlibFunction.kt

@@ -0,0 +1,2 @@
+fun fo<caret>o() {
+}