Make Array.size() a function instead of a property

Also add a deprecated extension property to help migration. This is done to
unify getting size of arrays and collections

core/reflection.jvm/src/kotlin/reflect/jvm/internal/foreignKClasses.kt

@@ -48,7 +48,7 @@ fun <T> foreignKotlinClass(jClass: Class<T>): KClassImpl<T> {
 
         // This is the most unlikely case: we found a cached array of references of length at least 2 (can't be 1 because
         // the single element would be cached instead), and none of those classes is the one we're looking for
-        val size = cached.size
+        val size = cached.size()
         // Don't use Array constructor because it creates a lambda
         val newArray = arrayOfNulls<WeakReference<KClassImpl<*>>>(size + 1)
         // Don't use Arrays.copyOf because it works reflectively