The number of physical GPUs to reserve for the agent container. This adds a GPU resource requirement to the
container definition, which is what makes ECS pin GPU devices to the container and run it with the GPU container runtime.
A 0 value means no GPU is requested.
Only supported with the EC2 launch type on GPU-enabled container instances (for example the Amazon ECS GPU-optimized AMI). It is not supported with the FARGATE launch type.