Fix task scheduling when multi_team is enabled

[vincbeck]

Summary

When multi_team is enabled, tasks remain in "No status" indefinitely and Dag runs never complete.

The root cause is that get_running_dag_runs_to_examine() returns a ScalarResult (a one-pass SQLAlchemy iterator). The multi-team code path added in #68108 iterates it to build a team-name mapping, exhausting the iterator before _schedule_all_dag_runs can consume it. As a result, zero Dag runs get processed and no task instances ever transition out of None state.

The fix materializes the ScalarResult into a list() so it can be safely iterated multiple times.

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