build(deps): bump serde_spanned from 0.6.3 to 0.6.4 (iopsystems#94)

Bumps [serde_spanned](https://github.com/toml-rs/toml) from 0.6.3 to 0.6.4.
- [Commits](toml-rs/toml@serde_spanned-v0.6.3...serde_spanned-v0.6.4)

---
updated-dependencies:
- dependency-name: serde_spanned
  dependency-type: indirect
  update-type: version-update:semver-patch
...

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