Collect state correctly if it's a function

[VladBrok]

The state could be a function:
https://github.com/vuejs/vuex/blob/v3.0.1/dist/vuex.js#L317-L319
so we should handle this case (both for module states and for the root state)

[euaaaio]

It looks like the first thing I should do is fix CI. Will do it in the next few days.

[euaaaio]

I’ve made some changes and fixed CI. Please update your branch.

[euaaaio]

Thanks 🖤
Will release it in the next few days.