Provide quick fix for migration of single elements in named arguments

See more in KT-20171

idea/testData/quickfix/surroundWithArrayOfForNamedArgumentsToVarargs/simpleNamedArgumentToVararg.kt

@@ -0,0 +1,8 @@
+// "Surround with *arrayOf(...)" "true"
+// LANGUAGE_VERSION: 1.2
+
+fun foo(vararg s: String) {}
+
+fun test() {
+    foo(s = <caret>"value")
+}