Bump vuex from 3.1.0 to 3.1.1

Bumps [vuex](https://github.com/vuejs/vuex) from 3.1.0 to 3.1.1.
- [Release notes](https://github.com/vuejs/vuex/releases)
- [Commits](https://github.com/vuejs/vuex/compare/v3.1.0...v3.1.1

)

Signed-off-by: dependabot[bot] <support@dependabot.com>
Signed-off-by: Christoph Wurst <christoph@winzerhof-wurst.at>