[dock] Only enable GPU if available

Some execution environments may run CPU as well as GPU
code, this check for Nvidia driver presence will allow
to reuse the same environment on both.

It also updates the GPU option to use the latest version
provided by the nvidia-docker2 documentation.
6 jobs for only_enable_gpu_runtime_if_available in 42 minutes and 33 seconds (queued for 3 seconds)
Status Job ID Name Coverage
  Build
passed #191140
docker-build
build_linux_36

00:13:30

64.0%
passed #191141
docker-build
build_linux_37

00:13:32

64.0%
passed #191156
macosx
build_macosx_36

00:14:38

64.0%
passed #191167
macosx
build_macosx_37

00:14:22

64.0%
failed #191138
macosx
build_macosx_36

00:21:24

64.0%
failed #191139
macosx
build_macosx_37

01:30:00

64.0%