Bump bigdecimal from 0.4.7 to 0.4.8

Bumps [bigdecimal](https://github.com/akubera/bigdecimal-rs) from 0.4.7 to 0.4.8.
- [Release notes](https://github.com/akubera/bigdecimal-rs/releases)
- [Commits](akubera/bigdecimal-rs@v0.4.7...v0.4.8)

---
updated-dependencies:
- dependency-name: bigdecimal
  dependency-version: 0.4.8
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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Author: dependabot[bot]