Add Bundle struct and request bundles in transaction task

[ss-es]

Closes #3381
Closes #3375

This PR:

• Adds the Bundle struct
• Adds a fetch_bundles method to the AuctionResultsProvider trait that retrieves a Bundle from all builders that win a given auction.
• Adds logic in the transactions task to call fetch_bundles and construct a PackedBundle from multiple builders depending on the version of HotShot in effect.
• Removes the bid_fees field from PackedBundle.

This PR does not:

Key places to review:

• task-impls/src/transactions.rs
• types/src/traits/auction_results_provider.rs