Minor, fix and unmute fieldNameClash.kt test

#KT-31927

compiler/testData/codegen/box/inlineClasses/fieldNameClash.kt

@@ -1,16 +1,9 @@
-// IGNORE_BACKEND_FIR: JVM_IR
-// IGNORE_BACKEND: JVM, JVM_IR, JS, JS_IR, NATIVE
-// IGNORE_BACKEND: JS_IR_ES6
-// There is a bug in the type mapper which results in an incorrect asm type for Z
-// when the names of the inline class backing field and an extension property clash.
-// https://youtrack.jetbrains.com/issue/KT-31927
-
 inline class Z(val s: String) {
     val Int.s: Int get() = 42
 }
 
 fun box(): String {
-    if (Z("a").toString() == "Z(s=\"a\")")
+    if (Z("a").toString() == "Z(s=a)")
         return "OK"
     return "Fail"
 }