Dockerfile.devel-gpu: optimize the size of the generated image (#15355)

- Use `nvidia/cuda:9.0-base-ubuntu16.04` as the base image to select
  just the CUDA libraries we need.
- Remove the installed static libraries.
- Remove the dependency on openjdk-8 since Bazel ships with a local copy.
- Perform a shallow clone of the repository.

The image is 2.94GB, down from 4.87GB.

Signed-off-by: Felix Abecassis <fabecassis@nvidia.com>