updates: add barrier for final last F36 next build

[dustymabe]

As discussed in the meeting today:
coreos/fedora-coreos-tracker#480 (comment)

[github-actions]

next
    version: 37.20220910.1.0 (latest)
    start: 2022-09-13 14:00:00+00:00 UTC (1 day, 11:22:30 ago)
           2022-09-13 10:00:00-04:00 Raleigh/New York/Toronto
           2022-09-13 16:00:00+02:00 Berlin/France/Poland
    duration: 4320m (72.0h)
stable
    version: 36.20220820.3.0 (latest)
    start: 2022-09-07 14:00:00+00:00 UTC (7 days, 11:22:30 ago)
           2022-09-07 10:00:00-04:00 Raleigh/New York/Toronto
           2022-09-07 16:00:00+02:00 Berlin/France/Poland
    duration: 2880m (48.0h)
testing
    version: 36.20220906.2.0 (latest)
    start: 2022-09-07 14:00:00+00:00 UTC (7 days, 11:22:30 ago)
           2022-09-07 10:00:00-04:00 Raleigh/New York/Toronto
           2022-09-07 16:00:00+02:00 Berlin/France/Poland
    duration: 2880m (48.0h)