l2geth: update timestamp logic

Update the assertion to not expect that the timestamps are
exactly equal but instead assert that the values are within
5%. This is because now the timestamps in L2 no longer
correspond to L1 timestamps and may be updated arbitrarily
by the sequencer.

This commit updates the timestamp updating logic
such that `time.Now` is used instead of relying on
L1 timestamps. This gives a higher fidelity for the
`TIMESTAMP` opcode as well as makes the time on L2
be closer to the time on L1.

L1 to L2 transactions no longer have the property of
having the same timestamp on L2 as the timestamp
of the L1 block they were included in.

This should be able to be turned on without needing
hardfork logic as replicas should always accept the
timestamp that the sequencer sets. The sequencer is
a trusted entity in the existing implementation and
it is expected that the sequencer will become more
trustless in future iterations of the protocol.

This change is added to improve both UX and devex.
Users are confused by the timestamps on Etherscan
being ~15 minutes behind. This is due to the timestamps
being set based on L1 block numbers, and the system
only pulls L1 data once a secure amount of PoW
is placed on top. Developers would like the timestamps
to have a higher fidelity and be closer to the timestamps
on L1.

go/batch-submitter: Metrics updates

- Renames a couple of metrics to include their units.
- Adds histogram buckets to `num_elements_per_batch`.
- Changes `batch_size_bytes` to a summary.
- Changes a couple of metrics to be gauges rather than counters.

Support multiple transactions in batch submitter

feat(proxyd): Add X-Forwarded-For header when proxying RPCs

feat(sdk): implement waitForMessageReceipt

feat(contracts): add in better gas oracle management

Updates the gas oracle hardhat task to also let it
manage the scalar and overhead.

go/stackman: Add stackman operator

feature - added op-exporter version metric

Converts Stackman into a Kube operator by adding the following:

- The basic Operator scaffolding. Things like RBAC, the manifests for the Operator itself, etc.
- CRDs for the DTL, Sequencer, Gas Oracle, Clique L1, batch submitter, deployer, and actors.

To see how the CRDs get used, see the nightly env in the stacks repo: https://github.com/ethereum-optimism/stacks/tree/master/nightly

Metadata:

- Fixes ENG-1673

Run dual tests for Synthetix

op-exporter version nil deference

integration-tests: Actor updates to run against nightly

- Modifies the existing actor tests to use predeployed contract addresses
- Exposes metrics about the actor via Prometheus

To see how the actors are set up using Stackman, see https://github.com/ethereum-optimism/stacks/blob/master/nightly/actors.yml.

Fixes ENG-1667

Remove logic for connecting contracts

Fixes codechecks reports