Consolidate `resolveConsentValue` functions between privacy center and fides-js

[allisonking]

Is your feature request related to a specific problem?

Both fides-js and privacy center have a resolveConsentValue function which are similar but not exactly the same.

Describe the solution you'd like

We should consolidate and have the privacy center use fides-js's version. this will require some refactoring since the input/output isn't exactly the same.

Describe alternatives you've considered, if any

A description of any alternative solutions or features you've considered.

Additional context

https://github.com/ethyca/fides/pull/3411#discussion_r1223235846