chore(deps): bump bls from 10a38a8 to 2a3c709 in /native/bls_nif

Bumps [bls](https://github.com/sigp/lighthouse) from `10a38a8` to `2a3c709`.
- [Release notes](https://github.com/sigp/lighthouse/releases)
- [Commits](sigp/lighthouse@10a38a8...2a3c709)

---
updated-dependencies:
- dependency-name: bls
  dependency-type: direct:production
...

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