The best way to play all songs by an Artist in shuffle mode is to access the Artist page and tap the green SHUFFLE PLAY button. If this doesn't work as expected make sure you restart the app and log out and back in to your Spotify account. Occasionally this is necessary to force a sync of info between your device and our account system.
If this persists, we recommend performing a clean reinstall of the Spotify app on your Android device to get the latest app version. This will also remove corrupted data that could be causing the issue.
It seems that I have never seen such a thing on any streaming service. That there was such a tab "all tracks" on the artist's pages. In the absence of such functionality, you can simply add the entire discography to your favorite = on the artist's page in the media library there will be all the tracks, since the albums are displayed there in expanded form. Or you can create your own playlist by adding all the discography there.