Adjust testData to isEmpty/key/value transformations

compiler/testData/codegen/box/builtinStubMethods/ListWithAllImplementations.kt

@@ -1,6 +1,6 @@
 class MyList<T>(val v: T): List<T> {
     override val size: Int get() = 0
-    override fun isEmpty(): Boolean = true
+    override val isEmpty: Boolean get() = true
     override fun contains(o: T): Boolean = false
     override fun iterator(): Iterator<T> = throw Error()
     override fun containsAll(c: Collection<T>): Boolean = false