5 minutes is too long and doesn't leave enough time after the retry to
still complete the job, especially if two boots fail in a row, removing
10 out of the worst-case 20 minutes allowed.
90 seconds is more than enough, the boot output normally starts after
~40-45 seconds.
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/30409>
38ede4334f