Bump tar from 6.2.0 to 6.2.1 in /test/express-postgres/app (#1018)

Bumps [tar](https://github.com/isaacs/node-tar) from 6.2.0 to 6.2.1.
- [Release notes](https://github.com/isaacs/node-tar/releases)
- [Changelog](https://github.com/isaacs/node-tar/blob/main/CHANGELOG.md)
- [Commits](isaacs/node-tar@v6.2.0...v6.2.1)

---
updated-dependencies:
- dependency-name: tar
  dependency-type: indirect
...

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

Author: dependabot[bot]