Do not create redundant special variance when enhancing types

#KT-8538 Fixed

compiler/testData/loadJava/compiledJava/mutability/ReadOnlyExtendsWildcard.txt

@@ -0,0 +1,6 @@
+package test
+
+public interface ReadOnlyExtendsWildcard {
+    public abstract fun bar(): kotlin.Unit
+    public abstract fun foo(/*0*/ org.jetbrains.annotations.ReadOnly() p0: kotlin.List<kotlin.CharSequence!>!, /*1*/ org.jetbrains.annotations.NotNull() p1: kotlin.Comparable<kotlin.String!>): kotlin.Unit
+}