submodules: bump external/oasis-core from ca29d1f to 364bff9

Bumps [external/oasis-core](https://github.com/oasisprotocol/oasis-core) from `ca29d1f` to `364bff9`.
- [Release notes](https://github.com/oasisprotocol/oasis-core/releases)
- [Commits](oasisprotocol/oasis-core@ca29d1f...364bff9)

---
updated-dependencies:
- dependency-name: external/oasis-core
  dependency-version: 364bff9e3e51dfbe1b38a110821d1f13441b0424
  dependency-type: direct:production
...

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Author: dependabot[bot]