build(deps): bump minimist, npm, handlebars and mkdirp

Bumps [minimist](https://github.com/minimistjs/minimist), [npm](https://github.com/npm/cli), [handlebars](https://github.com/handlebars-lang/handlebars.js) and [mkdirp](https://github.com/isaacs/node-mkdirp). These dependencies needed to be updated together.

Updates `minimist` from 1.2.0 to 1.2.8
- [Changelog](https://github.com/minimistjs/minimist/blob/main/CHANGELOG.md)
- [Commits](minimistjs/minimist@v1.2.0...v1.2.8)

Updates `npm` from 6.4.1 to 6.14.18
- [Release notes](https://github.com/npm/cli/releases)
- [Changelog](https://github.com/npm/cli/blob/v6.14.18/CHANGELOG.md)
- [Commits](npm/cli@v6.4.1...v6.14.18)

Updates `handlebars` from 4.0.12 to 4.7.8
- [Release notes](https://github.com/handlebars-lang/handlebars.js/releases)
- [Changelog](https://github.com/handlebars-lang/handlebars.js/blob/v4.7.8/release-notes.md)
- [Commits](handlebars-lang/handlebars.js@v4.0.12...v4.7.8)

Updates `mkdirp` from 0.5.1 to 0.5.6
- [Changelog](https://github.com/isaacs/node-mkdirp/blob/main/CHANGELOG.md)
- [Commits](isaacs/node-mkdirp@0.5.1...v0.5.6)

---
updated-dependencies:
- dependency-name: minimist
  dependency-type: indirect
- dependency-name: npm
  dependency-type: indirect
- dependency-name: handlebars
  dependency-type: indirect
- dependency-name: mkdirp
  dependency-type: indirect
...

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