## Issue Addressed
Which issue # does this PR address?
#2629
## Proposed Changes
Please list or describe the changes introduced by this PR.
1. ci would dowload the bls test cases from https://github.com/ethereum/bls12-381-tests/
2. all the bls test cases(except eth ones) would use cases in the archive from step one
3. The bls test cases from https://github.com/ethereum/consensus-spec-tests would stay there and no use . For the future , these bls test cases would be remove suggested from https://github.com/ethereum/consensus-spec-tests/issues/25 . So it would do no harm and compatible for future cases.
## Additional Info
Please provide any additional information. For example, future considerations
or information useful for reviewers.
Question:
I am not sure if I should implement tests about `deserialization_G1`, `deserialization_G2` and `hash_to_G2` for the issue.
## Proposed Changes
Implement the consensus changes necessary for the upcoming Altair hard fork.
## Additional Info
This is quite a heavy refactor, with pivotal types like the `BeaconState` and `BeaconBlock` changing from structs to enums. This ripples through the whole codebase with field accesses changing to methods, e.g. `state.slot` => `state.slot()`.
Co-authored-by: realbigsean <seananderson33@gmail.com>
