Remove unneeded background and update the background color to reflect light/night theme

Updating the background color is a temporary workaround until we get all
the images for phone/tablet, light/night theme with correct size

Bug: 324312956
Test: manual (check the image in dark theme)
Flag: EXEMPT no flaggable resource change
Change-Id: I888e28825bdf9fd5ceffdf47386500ad6288b271

src/com/android/settings/accessibility/AccessibilityShortcutsTutorial.java

@@ -460,6 +460,8 @@ public final class AccessibilityShortcutsTutorial {
         final View image =
                 createIllustrationView(context,
                         R.drawable.a11y_shortcut_type_quick_settings);
+        // Remove the unneeded background, since the main image already includes a background
+        image.findViewById(R.id.image_background).setVisibility(GONE);
         final int numFingers = AccessibilityUtil.isTouchExploreEnabled(context) ? 2 : 1;
         Map<String, Object> arguments = new ArrayMap<>();
         arguments.put("count", numFingers);