Prohibit assigning single elements into varargs in named form

#KT-20588 Fixed
 #KT-20589 Fixed

idea/testData/quickfix/replaceWithArrayCallInAnnotation/replaceForbiddenAssignmentWithArrayLiteral.kt

@@ -0,0 +1,8 @@
+// "Replace with array call" "true"
+// COMPILER_ARGUMENTS: -XXLanguage:+ProhibitAssigningSingleElementsToVarargsInNamedForm
+// DISABLE-ERRORS
+
+annotation class Some(vararg val strings: String)
+
+@Some(strings = <caret>"value")
+class My

idea/testData/quickfix/replaceWithArrayCallInAnnotation/replaceForbiddenAssignmentWithArrayLiteral.kt.after

@@ -0,0 +1,8 @@
+// "Replace with array call" "true"
+// COMPILER_ARGUMENTS: -XXLanguage:+ProhibitAssigningSingleElementsToVarargsInNamedForm
+// DISABLE-ERRORS
+
+annotation class Some(vararg val strings: String)
+
+@Some(strings = ["value"])
+class My