EVM/Sequencer: version data-dir and perform migration

Context

This puts a version file in the data-dir. Therefore if we make breaking changes and we need to migrate we just need to bump the version and write the migration code. I'm not a huge fan of where is located the code, but I believe it has to be in evm_context.ml to avoid circular dependencies etc

Manually testing the MR

$ ./octez-evm-node run sequencer with endpoint https://rollup-node.2024-02-12.etherlink-nightly.tzalpha.net/ signing with <sk> --data-dir /tmp/evm-node-data-dir --rpc-addr 0.0.0.0 --rpc-port 8545 --time-between-blocks none --initial-kernel sequencer.wasm

produced a few blocks:

$ curl -X POST -H 'Content-Type: application/json' --data '{"id":28303029412179935,"jsonrpc":"2.0","method":"produceBlock"}'  http://localhost:8546/private
$ curl -X POST -H 'Content-Type: application/json' --data '{"id":28303029412179935,"jsonrpc":"2.0","method":"produceBlock"}'  http://localhost:8546/private
$ curl -X POST -H 'Content-Type: application/json' --data '{"id":28303029412179935,"jsonrpc":"2.0","method":"produceBlock"}'  http://localhost:8546/private

then:

$ ./octez-evm-node run sequencer with endpoint https://rollup-node.2024-02-12.etherlink-nightly.tzalpha.net/ signing with <sk> --data-dir /tmp/evm-node-data-dir --rpc-addr 0.0.0.0 --rpc-port 8545 --time-between-blocks none --initial-kernel sequencer.wasm **--devmode**

If the migration do not happen, you'll produce the block genesis again.

Checklist

• Document the interface of any function added or modified (see the coding guidelines)
• Document any change to the user interface, including configuration parameters (see node configuration)
• Provide automatic testing (see the testing guide).
• For new features and bug fixes, add an item in the appropriate changelog (docs/protocols/alpha.rst for the protocol and the environment, CHANGES.rst at the root of the repository for everything else).
• Select suitable reviewers using the Reviewers field below.
• Select as Assignee the next person who should take action on that MR