docs(splash): Update preferences TOC (#1382)

- Adds SplashScreenBackgroundColor
- Removes ShowSplashScreenSpinner
diff --git a/www/docs/en/dev/core/features/splashscreen/index.md b/www/docs/en/dev/core/features/splashscreen/index.md
index 8bbe616..1ae157e 100644
--- a/www/docs/en/dev/core/features/splashscreen/index.md
+++ b/www/docs/en/dev/core/features/splashscreen/index.md
@@ -44,8 +44,8 @@
     - [`AutoHideSplashScreen`](#autohidesplashscreen)
     - [`FadeSplashScreen`](#fadesplashscreen)
     - [`FadeSplashScreenDuration`](#fadesplashscreenduration)
-    - [`ShowSplashScreenSpinner`](#showsplashscreenspinner)
     - [`SplashScreenDelay`](#splashscreendelay)
+    - [`SplashScreenBackgroundColor`](#splashscreenbackgroundcolor)
     - [`AndroidPostSplashScreenTheme`](#androidpostsplashscreentheme)
     - [`AndroidWindowSplashScreenAnimatedIcon`](#androidwindowsplashscreenanimatedicon)
     - [`AndroidWindowSplashScreenAnimationDuration`](#androidwindowsplashscreenanimationduration)