Update documentation with how to display icons on splash screens on Splash Screen page.

[suman-somu]

On following the documentation of adding a splash screen, I couldn't get the result. I added each respective dpi icon and changed the icon in styles.xml I tested it in both android 13 and android 12 with the respective code.

The thing which worked for me was changing the icon from default to my own in AndroidManifest. It changed the icon and showed the splash screen correctly.

<application
        android:label="instgram_clone"
        android:name="${applicationName}"
        android:icon="@mipmap/images">

I don't know why it worked like this. But if it's required, then add as a step in docs.