Don't access activity after close

[sentry-io]

Sentry Issue: ANDROID-69

WindowManager$BadTokenException: Unable to add window -- token android.os.BinderProxy@3e69623 is not valid; is your activity running?
    at android.view.ViewRootImpl.setView(ViewRootImpl.java:959)
    at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:387)
    at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:95)
    at android.app.Dialog.show(Dialog.java:342)
    at androidx.appcompat.app.AlertDialog$Builder.show(AlertDialog.java:1009)
...
(9 additional frame(s) were not displayed)