Bump source-map-support from 0.5.19 to 0.5.21 (#540)

Bumps [source-map-support](https://github.com/evanw/node-source-map-support) from 0.5.19 to 0.5.21.
- [Release notes](https://github.com/evanw/node-source-map-support/releases)
- [Commits](evanw/node-source-map-support@v0.5.19...v0.5.21)

---
updated-dependencies:
- dependency-name: source-map-support
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

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