Fix IllegalStateException after onSaveInstanceState

[Stypox]

What is it?

• Bugfix (user facing)
• Feature (user facing)
• Codebase improvement (dev facing)
• Meta improvement to the project (dev facing)

Description of the changes in your PR

This PR fixes a random crash happening sometimes when messing with the miniplayer while it's still starting. According to this SO the solution is just to replace commit() with commitAllowingStateLoss(), which may not be a real solution (state loss should never happen in theory) but is surely better than making the app crash completely.

This was the stack trace:

java.lang.IllegalStateException: Can not perform this action after onSaveInstanceState
        at androidx.fragment.app.FragmentManager.checkStateLoss(FragmentManager.java:1691)
        at androidx.fragment.app.FragmentManager.enqueueAction(FragmentManager.java:1731)
        at androidx.fragment.app.BackStackRecord.commitInternal(BackStackRecord.java:321)
        at androidx.fragment.app.BackStackRecord.commit(BackStackRecord.java:286)
        at org.schabi.newpipe.util.NavigationHelper.showMiniPlayer(NavigationHelper.java:409)
        at org.schabi.newpipe.MainActivity$3.onReceive(MainActivity.java:822)
        at android.app.LoadedApk$ReceiverDispatcher$Args.run(LoadedApk.java:1218)
        at android.os.Handler.handleCallback(Handler.java:761) 
        at android.os.Handler.dispatchMessage(Handler.java:98) 
        at android.os.Looper.loop(Looper.java:156) 
        at android.app.ActivityThread.main(ActivityThread.java:6517) 
        at java.lang.reflect.Method.invoke(Native Method) 
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:942) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:832) 

APK testing

app-debug.zip

Due diligence

• I read the contribution guidelines.

[TobiGr]

Looks good to me