Bump @vue/cli-plugin-vuex from 5.0.4 to 5.0.8

Bumps [@vue/cli-plugin-vuex](https://github.com/vuejs/vue-cli/tree/HEAD/packages/@vue/cli-plugin-vuex) from 5.0.4 to 5.0.8.
- [Release notes](https://github.com/vuejs/vue-cli/releases)
- [Changelog](https://github.com/vuejs/vue-cli/blob/dev/CHANGELOG.md)
- [Commits](https://github.com/vuejs/vue-cli/commits/v5.0.8/packages/@vue/cli-plugin-vuex)

---
updated-dependencies:
- dependency-name: "@vue/cli-plugin-vuex"
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

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