Bump ejs and grunt-contrib-nodeunit

Bumps [ejs](https://github.com/mde/ejs) to 3.1.8 and updates ancestor dependency [grunt-contrib-nodeunit](https://github.com/gruntjs/grunt-contrib-nodeunit). These dependencies need to be updated together.


Updates `ejs` from 2.7.4 to 3.1.8
- [Release notes](https://github.com/mde/ejs/releases)
- [Changelog](https://github.com/mde/ejs/blob/main/CHANGELOG.md)
- [Commits](mde/ejs@v2.7.4...v3.1.8)

Updates `grunt-contrib-nodeunit` from 2.1.0 to 4.0.0
- [Release notes](https://github.com/gruntjs/grunt-contrib-nodeunit/releases)
- [Changelog](https://github.com/gruntjs/grunt-contrib-nodeunit/blob/main/CHANGELOG)
- [Commits](gruntjs/grunt-contrib-nodeunit@v2.1.0...v4.0.0)

---
updated-dependencies:
- dependency-name: ejs
  dependency-type: indirect
- dependency-name: grunt-contrib-nodeunit
  dependency-type: direct:development
...

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