[UX] Change the default `retry` policy to infinitely retry on `no-capacity`

[peterschmidt85]

By default, runs have no retry policy. If a run can’t find capacity at submission time, it fails with no offers.

In most cases, this isn’t the desired default. A more useful default is to queue the run until capacity becomes available. If you prefer a different behavior—for example, fail immediately when no offers are available—specify it explicitly:

retry:
  on_events: []

[!NOTE] The off value for duration means - "infinite" (no limit).