Bump parity-scale-codec from 3.1.3 to 3.1.5 (#1356)

Bumps [parity-scale-codec](https://github.com/paritytech/parity-scale-codec) from 3.1.3 to 3.1.5.
- [Release notes](https://github.com/paritytech/parity-scale-codec/releases)
- [Changelog](https://github.com/paritytech/parity-scale-codec/blob/master/CHANGELOG.md)
- [Commits](https://github.com/paritytech/parity-scale-codec/compare/parity-scale-codec-3.1.3...parity-scale-codec-3.1.5)

---
updated-dependencies:
- dependency-name: parity-scale-codec
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>