[Snyk] Upgrade webpack-cli from 4.7.2 to 4.9.1

Snyk has created this PR to upgrade webpack-cli from 4.7.2 to 4.9.1.

merge advice :information_source: Keep your dependencies up-to-date. This makes it easier to fix existing vulnerabilities and to more quickly identify and fix newly disclosed vulnerabilities when they affect your project.

The recommended version is 3 versions ahead of your current version.
The recommended version was released 3 months ago, on 2021-10-18.

Release notes

Package name: webpack-cli

4.9.1 - 2021-10-18
4.9.1 (2021-10-18)

Bug Fixes
- compatibility with dynamic import (#3006) (6a9aac9)
4.9.0 - 2021-10-06
4.9.0 (2021-10-06)

Bug Fixes
- handle undefined and empty configuration export (#2930) (9b9040e)
Features
- allow to run commands without webpack installation where it is unnecessary (#2907) (603041d)
4.8.0 - 2021-08-15
4.8.0 (2021-08-15)

Bug Fixes
- show default value in help output if available (#2814) (7f50948)
- support top multi compiler options (#2874) (82b1fb7)
Features
- show possible values for option in help output (#2819) (828e5c9)
- init-generator: add ability to specify a package manager of choice (#2769) (e53f164)
4.7.2 - 2021-06-07