Fix the bug that AsyncImage demo cannot update new images in tutorials/Image_And_Icons_Manipulations/README.md

[hehua2008]

val image: T? by produceState<T?>()

should use "load" as a key, or else it won't be re-launched for the new "load".

-     val image: T? by produceState<T?>(null) {
+     val image: T? by produceState<T?>(null, load) {
         value = withContext(Dispatchers.IO) {
             try {
                 load()
             } catch (e: IOException) {
                 // instead of printing to console, you can also write this to log,
                 // or show some error placeholder
                 e.printStackTrace()
                 null
             }
         }
     }

And

painterFor = { remember { BitmapPainter(it) } }

should use "it" as a key for the "remember", or else the "painterFor" won't update for the new "image" loaded by "produceState".

         AsyncImage(
             load = { loadImageBitmap(File("sample.png")) },
-            painterFor = { remember { BitmapPainter(it) } },
+            painterFor = { remember(it) { BitmapPainter(it) } },
             contentDescription = "Sample",
             modifier = Modifier.width(200.dp)
         )

[hehua2008]

Please fix this bug to avoid confusing tutorials learners!