GitLab

* Fix benchmark time measurement

* Reduce batch size for bench_rgcn_homogeneous_ns am

bench_rgcn_homogeneous_ns am data sample size is too small for 1024 batch size
Co-authored-by: Rhett Ying <85214957+Rhett-Ying@users.noreply.github.com>
Co-authored-by: Quan (Andy) Gan <coin2028@hotmail.com>