Cache bundle-to-team name lookups in dag processor manager

[ferruzzi]

Follow-up to request by @o-nikolas in #68599 to add caching like we did in the scheduler.

Adding a _bundle_name_to_team_name map/cache and a _multi_team flag (read once at construction, like the scheduler) on DagFileProcessorManager also allowed me to move the if multi-team check into the _get_team_names() and _get_team_name() helpers, simplifying the calling code.

The cache/map is cleared inside the _refresh_dag_bundles() method, which is the only time we can pick up new mappings anyway.

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[seanghaeli]

Verified in breeze that the cache produces correct results, invalidation works, the n->1 query batching works, and a bundle can't be mapped to a second team