Bump winston from 3.14.2 to 3.15.0 (#308)

Bumps [winston](https://github.com/winstonjs/winston) from 3.14.2 to 3.15.0.
- [Release notes](https://github.com/winstonjs/winston/releases)
- [Changelog](https://github.com/winstonjs/winston/blob/master/CHANGELOG.md)
- [Commits](winstonjs/winston@v3.14.2...v3.15.0)

---
updated-dependencies:
- dependency-name: winston
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: George M. Dias <gdias@mitre.org>