Bump minimist from 1.2.5 to 1.2.6 in /examples/grpc/hello-world

Bumps [minimist](https://github.com/substack/minimist) from 1.2.5 to 1.2.6.
- [Release notes](https://github.com/substack/minimist/releases)
- [Commits](https://github.com/substack/minimist/compare/1.2.5...1.2.6)

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

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

Author: dependabot[bot]