Allow resetting the `solutions` object, or setting it to undefined for any subsequent call.

[Tbaut]

When using the react sdk and our hooks, I figured that the fact that we have no promise for the getPoolAssetOnDestination for instance, and rather wait for solutions to not be undefined makes it so that if the user changes their input (and hence it changes the params for the api calls) then the solutions will be outdated for the time until the api responds.

Ideally, we should have a reset param that we could call, and that would set the solutions to undefined.
Or we should make sure the solutions is undefined before we do a call to the api, just like we set the loading to true.

What do you think?

[saadahmsiddiqui]

IMO rather than storing solution state within the SDK it'd be better to "promisify" it and let devs handle it themselves?