* contracts-bedrock: less compiler warnings

Cleans up compiler warnings that were introduced in https://github.com/ethereum-optimism/optimism/pull/2938.
A bunch of unused variables are deleted, reverts are being asserted on
so no need to assign variables.

* contracts-bedrock: regenerate snapshot
Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>