[BUG] `overmind-react` - multiple overmind named instances

[nkint]

Hi!
Thanks for the great library.

The documentations says here:

If you have multiple instances of Overmind on the same page you can name your app to differentiate them

But it's not clear to me how to correctly achieve this.

I want two separate states, and I created for each one of them a state/actions/config + a createOvermind method+ React hooks + a Provider.
Only one of them is correctly read by the component that needs data from both overmind instances.
Here there is a dumb example to reproduce the problem:
https://codesandbox.io/s/overmind-multiple-named-instances-forked-i5biot?file=/src/index.tsx

I'm sure I'm doing it wrong but documentations lacks or there is a bug.
I understand that I can use namespace but it doesn't fit my case.

[nkint]

I think that the problem relies in overmind-react and in how react context works.

This can be seen as a related problem: #477