Bump minimatch from 3.0.4 to 3.1.2 in /demo

Bumps [minimatch](https://github.com/isaacs/minimatch) from 3.0.4 to 3.1.2.
- [Release notes](https://github.com/isaacs/minimatch/releases)
- [Commits](isaacs/minimatch@v3.0.4...v3.1.2)

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

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

Author: dependabot[bot]