replay: Replace collision aware policy with retry proxy storage configuration

As it's now integrated within the retry proxy storage.

Related to swh-storage!924 (closed)

Note:

• tests will fail because swh-storage!924 (closed) needs to be merged and storage bumped first.
• This conflicts with swh-storage!927 (closed) (which moves the replayer in the storage). So this should be diffed against the storage when swh-storage!927 (closed) lands.

Test Plan

tox (will be happy at some point in time)

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Migrated from D3015 (view on Phabricator)