GitLab

* replace dgl PRNG with pcg32

* remove pcg submodule, add a simple implementation

* replace pcg32 with std::mt19937_64

* fix include order

* change RandomEngine to pcg32

* Remove custom pcg32 implementation, use the submodule provided by the original author.

* minor bug

* move include for linting

* include pcg for tests too
Co-authored-by: Hongzhi (Steve), Chen <chenhongzhi.nkcs@gmail.com>