Bump braces and grunt-cli in /slides

Bumps [braces](https://github.com/micromatch/braces) to 3.0.3 and updates ancestor dependency [grunt-cli](https://github.com/gruntjs/grunt-cli). These dependencies need to be updated together.


Updates `braces` from 3.0.2 to 3.0.3
- [Changelog](https://github.com/micromatch/braces/blob/master/CHANGELOG.md)
- [Commits](micromatch/braces@3.0.2...3.0.3)

Updates `grunt-cli` from 1.3.2 to 1.4.3
- [Release notes](https://github.com/gruntjs/grunt-cli/releases)
- [Changelog](https://github.com/gruntjs/grunt-cli/blob/main/CHANGELOG.md)
- [Commits](gruntjs/grunt-cli@v1.3.2...v1.4.3)

---
updated-dependencies:
- dependency-name: braces
  dependency-type: indirect
- dependency-name: grunt-cli
  dependency-type: direct:development
...

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

Author: dependabot[bot]