How to load image in tests with RobolectricTestRunner?

[Samuel-Unknown]

I don't understand ow to do it.
I've tried:

@RunWith(RobolectricTestRunner::class)
@Config(sdk = [Build.VERSION_CODES.M])
class ImageLoadingTest {

   private val appContext = RuntimeEnvironment.getApplication()
   private lateinit var imageLoader: ImageLoader

   @Before
   fun init() {
      imageLoader =  ImageLoader.Builder(appContext).build()
   }

   @Test
   fun fillAndClearCache() = runTest {
      val request = ImageRequest.Builder(appContext)
            .data(url)
            .build()

      imageLoader.execute(request)
   }
}

but I see the error: "After waiting for 60000 ms, the test coroutine is not completing"

What I'm doing wrong?