* op-bindings: delete more dead code

Remove more dead code from the `op-bindings` package.
The only thing left are the generated bindings themselves
which can be moved to the packages that depend on them.
`op-e2e` may be the only remaining package that depends
on bindings.

The predeploy addresses still exist, there is a question
as to where they should live. Perhaps in `op-node` since
they are consensus critical parameters.

The etherscan client was moved into `op-chain-ops` because
it could be useful in the future but it should also be deleted
if it ends up not being used at all.

* indexer: fix build