[Sequencer/RPC] L1 data is not polled when the network is halted

[hexoscott]

During a network upgrade we set the sequencer to halt at a batch height. Once this has been done we wait for the L1 data to be finalised before continuing. The sequencer/RPC should report the latest batch as verified at this point but it is reporting old data.

The problem here is likely that changes to the batches / sequencer execution stages are stopping the stage loop from running as normal when the network is halted so no new L1 data is being collected. We need to ensure a halted network is still checking the L1 for new information.