Update to latest NCCL (2.3.7-1) for CUDA 10.0

Status Job ID Name Coverage
  Cuda
passed #119576137
v10.0

00:09:56

passed #119576136
v8.0

00:05:36

 
  Cudnn
passed #119576141
v10.0-cudnn7

00:08:03

passed #119576138
v8.0-cudnn5

00:03:37

passed #119576139
v8.0-cudnn6

00:04:19

passed #119576140
v8.0-cudnn7

00:04:12