Let's see if we can make these tests stable (#6241)

* Let's see if we can make these tests stable

* Also handle this for ImageButtonStub

src/Core/tests/DeviceTests/Handlers/Image/ImageHandlerTests.cs

@@ -127,7 +127,7 @@ namespace Microsoft.Maui.DeviceTests
 			{
 				var handler = (IPlatformViewHandler)CreateHandler(image);
 
-				await image.Wait();
+				await image.Wait(timeout: 5000);
 
 #if __ANDROID__
 				handler.PlatformView.SetMinimumHeight(1);
@@ -137,8 +137,6 @@ namespace Microsoft.Maui.DeviceTests
 				await handler.PlatformView.AssertContainsColor(color);
 			});
 
-			await Task.Delay(1000);
-
 			Assert.Equal(new List<string> { "LoadingStarted", "LoadingFailed" }, order);
 			Assert.NotNull(exception);
 		}

src/Core/tests/DeviceTests/Stubs/ImageButtonStub.cs

@@ -37,15 +37,23 @@ namespace Microsoft.Maui.DeviceTests.Stubs
 		public void UpdateIsLoading(bool isLoading) =>
 			IsLoading = isLoading;
 
-		void IImageSourcePartEvents.LoadingCompleted(bool successful) =>
+		void IImageSourcePartEvents.LoadingCompleted(bool successful)
+		{
+			IsLoading = false;
 			LoadingCompleted?.Invoke(successful);
+		}
 
-		void IImageSourcePartEvents.LoadingFailed(Exception exception) =>
+		void IImageSourcePartEvents.LoadingFailed(Exception exception)
+		{
+			IsLoading = false;
 			LoadingFailed?.Invoke(exception);
+		}
 
-		void IImageSourcePartEvents.LoadingStarted() =>
+		void IImageSourcePartEvents.LoadingStarted()
+		{
+			IsLoading = true;
 			LoadingStarted?.Invoke();
-
+		}
 
 		public event EventHandler Pressed;
 		public event EventHandler Released;

src/Core/tests/DeviceTests/Stubs/ImageStub.cs

@@ -22,14 +22,23 @@ namespace Microsoft.Maui.DeviceTests.Stubs
 		public void UpdateIsLoading(bool isLoading) =>
 			IsLoading = isLoading;
 
-		void IImageSourcePartEvents.LoadingCompleted(bool successful) =>
+		void IImageSourcePartEvents.LoadingCompleted(bool successful)
+		{
+			IsLoading = false;
 			LoadingCompleted?.Invoke(successful);
+		}
 
-		void IImageSourcePartEvents.LoadingFailed(Exception exception) =>
+		void IImageSourcePartEvents.LoadingFailed(Exception exception)
+		{
+			IsLoading = false;
 			LoadingFailed?.Invoke(exception);
+		}
 
-		void IImageSourcePartEvents.LoadingStarted() =>
+		void IImageSourcePartEvents.LoadingStarted()
+		{
+			IsLoading = true;
 			LoadingStarted?.Invoke();
+		}
 	}
 
 	public static class ImageStubExtensions