deps: bump libp2p-identity from 0.2.8 to 0.2.9

Bumps [libp2p-identity](https://github.com/libp2p/rust-libp2p) from 0.2.8 to 0.2.9.
- [Release notes](https://github.com/libp2p/rust-libp2p/releases)
- [Changelog](https://github.com/libp2p/rust-libp2p/blob/master/CHANGELOG.md)
- [Commits](https://github.com/libp2p/rust-libp2p/commits)

---
updated-dependencies:
- dependency-name: libp2p-identity
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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