Insert solid_selection into pipeline snapshots in sorted order

Summary: Resolves https://github.com/dagster-io/dagster/issues/4426 - unless there is a specific reason its important to store these in the order they were entered for some reason, inserting them deterministically is needed in order to be able to safely ensure that the same pipeline always has the same snapshot

Test Plan: BK, run test_backfill_from_failure_for_subselection 20 times, no more deterministic failure

Reviewers: alangenfeld, yuhan, prha

Reviewed By: prha

Differential Revision: https://dagster.phacility.com/D9168