Bump flatted and vuex-persist

Bumps [flatted](https://github.com/WebReflection/flatted) to 3.4.2 and updates ancestor dependency [vuex-persist](https://github.com/championswimmer/vuex-persist). These dependencies need to be updated together.


Updates `flatted` from 3.3.3 to 3.4.2
- [Commits](WebReflection/flatted@v3.3.3...v3.4.2)

Updates `vuex-persist` from 2.3.0 to 3.1.3
- [Changelog](https://github.com/championswimmer/vuex-persist/blob/master/CHANGELOG.md)
- [Commits](championswimmer/vuex-persist@v2.3.0...v3.1.3)

---
updated-dependencies:
- dependency-name: flatted
  dependency-version: 3.4.2
  dependency-type: indirect
- dependency-name: vuex-persist
  dependency-version: 3.1.3
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

package-lock.json

@@ -36,7 +36,7 @@
     "vue-router": "^4.4.0",
     "vue-select": "4.0.0-beta.6",
     "vuex": "^4.1.0",
-    "vuex-persist": "^2.2.0"
+    "vuex-persist": "^3.1.3"
   },
   "devDependencies": {
     "@types/lodash": "^4.14.179",