find_observation_states takes contact_network as an argument but never uses it

[dburov190]

Here
https://github.com/dburov190/risk-networks/blob/8d8bbfc0b61621d9ef48df22b33251dd8f386b64/epiforecast/measurements.py#L136-L139

contact_network is being passed into find_observation_states but is never used; is this a bug (and it should be used in some way) or is it safe to remove contact_network from the argument list?

[odunbar]

This is here because it is possible that we wish to target observations not only based on their current risk, but also the degree of the node.

[odunbar]

If you would like more consistency we could create an observation which uses it.

[dburov190]

I'd say the cleanest way is to simply delete it here and when (and if!) we ever need it, implement it then. Chances are, we'll never need it, and having an argument in a function that's never used is confusing.