[Refactor] Unifying the API for computing Lagrange Polynomials

[chancharles92]

Goal: have a unified and efficient implementation/API for computing the polynomial given n point-evaluation pairs. E.g., the following two places are inlining different code for the same functionality. https://github.com/EspressoSystems/jellyfish/blob/1a9db506f011b168ead863e1dfcb5fd094fa2550/primitives/src/reed_solomon_code/mod.rs#L89-L95 https://github.com/EspressoSystems/jellyfish/blob/kzg-multiproof-binyi/primitives/src/pcs/univariate_kzg/mod.rs#L621