Update to bls12-381.3.0.1

Context

Depends on opam-repository!256 (merged).

!4574 (closed) updates to bls12-381.3.0.0, and is built on top of !4503 (merged). However, they can not be merged before the activation of Ithaca, and @hhugo1 (see !4574 (comment 866546119) and Slack messages) and @lrand (see !4596 (comment 870344420)) would benefit from it.

I will close !4574 (closed) in favor of this one. 3.0.1 introduces a fix @lrand needs for !4596 (merged). !4503 (merged) will need to be rebased when this one is merged and Ithaca is activated on mainnet.

Manually testing the MR

N/A

Checklist

• N/A Document the interface of any function added or modified (see the coding guidelines)
• N/A Document any change to the user interface, including configuration parameters (see node configuration)
• Provide automatic testing (see the testing guide).
• N/A 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