Pre cancel retrievals that will fail due to identical miner and payload CID

[hannahhoward]

Goals

When a previous retrieval with the same payload CID & miner is stuck and running indefinitely, cancel it before attempting the deal, so the deal doesn't fail.

Implementation

• Update Lotus (we need a commit sha that has ClientListRetrievals -- not this does for our dealbots to run on almost master code of Lotus -- but the SHA used is the one we're running infra)
• I also had to pull in a new updated ffi-stub
• On deal start, list all retrievals, iterate through to check for any that have the same miner (peer.ID) and payloadCID, and cancel them if so -- this is the same logic used internally by go-fil-markets to produce the error so should be reliable

For Discussion

fixes #156