Clean up CUDA 11.6 Docker images (#98395)
We need to clean up 11.6 on PyTorch too after https://github.com/pytorch/builder/pull/1366. Otherwise, docker build would fail with a `bad argument 11.6` error, i.e. https://github.com/pytorch/pytorch/actions/runs/4614525312/jobs/8159595038
Pull Request resolved: https://github.com/pytorch/pytorch/pull/98395
Approved by: https://github.com/atalman, https://github.com/malfet
