fix: prevent atom effect from overwriting state when batching set's

[bartvanremortele]

Fixes #35

[polemius]

Thank you for PR. I have run test against this PR and these two are failing:

Storage: async
    ✕ should remove key from storage if reset (83 ms)
    ✕ should update storage if using atomFamily (16 ms)

Could you please check it?

[insaindesign]

It's a little ugly, but i had a go at fixing this for async storage: insaindesign@0811319.

Note it depends on the changes I had made in https://github.com/polemius/recoil-persist/pull/55/files (all storage to async).