Extraction Engine: Skip named argument references while analyzing extractable code

#KT-6896 Fixed

idea/testData/refactoring/extractFunction/parameters/misc/namedArguments.kt

@@ -0,0 +1,9 @@
+// PARAM_TYPES: kotlin.String
+// PARAM_DESCRIPTOR: val a: kotlin.String defined in main
+
+fun main(args: Array<String>) {
+    val a = "sdfsf"
+    <selection>a.def(a = 1, b = "")</selection>
+}
+
+fun String.def(a: Int = 1, b: String) {}

idea/testData/refactoring/extractFunction/parameters/misc/namedArguments.kt.after

@@ -0,0 +1,13 @@
+// PARAM_TYPES: kotlin.String
+// PARAM_DESCRIPTOR: val a: kotlin.String defined in main
+
+fun main(args: Array<String>) {
+    val a = "sdfsf"
+    __dummyTestFun__(a)
+}
+
+private fun __dummyTestFun__(a: String) {
+    a.def(a = 1, b = "")
+}
+
+fun String.def(a: Int = 1, b: String) {}