[FEA] Laplacian normalization primitive

[aamijar]

#2568 introduced a laplacian primitive in raft. We should also add a primitive for normalized laplacian which is used for spectral embedding.

This should be equivalent to normed=True in scipy.
https://docs.scipy.org/doc/scipy/reference/generated/scipy.sparse.csgraph.laplacian.html#scipy.sparse.csgraph.laplacian