Bump sequencer-utils from 8caa334 to d12d4b7

Bumps [sequencer-utils](https://github.com/EspressoSystems/espresso-sequencer) from `8caa334` to `d12d4b7`.
- [Release notes](https://github.com/EspressoSystems/espresso-sequencer/releases)
- [Commits](EspressoSystems/espresso-sequencer@8caa334...d12d4b7)

---
updated-dependencies:
- dependency-name: sequencer-utils
  dependency-type: direct:production
...

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