chore(deps): bump terser from 4.6.3 to 4.8.1 in /superset-frontend

Bumps [terser](https://github.com/terser/terser) from 4.6.3 to 4.8.1.
- [Release notes](https://github.com/terser/terser/releases)
- [Changelog](https://github.com/terser/terser/blob/master/CHANGELOG.md)
- [Commits](https://github.com/terser/terser/commits)

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

Signed-off-by: dependabot[bot] <[email protected]>