Harvest remaining old ThetaGPU docs pages and clean up sophia/not_in_nav

[felker]

Leftover from Sophia documentation launch about 6 months ago. Should delete any old ThetaGPU files that dont have anything useful or relevant to pull into the current Sophia documentation that is visible in the sidebar:

❯ pwd
/Users/felker/Desktop/user-guides/docs/sophia/not_in_nav
❯ wc -l **/*.md | sort
    14 data-science/data-science-software-availability.md
    17 performance-tools/darshan.md
    26 data-science/gpu-monitoring.md
    37 data-science/dl-frameworks/tensorboard-instructions.md
    39 data-science/pythonc-code-interoperability.md
    46 data-science/gpu-node-queue-and-policy.md
    49 programming-models/kokkos.md
    54 programming-models/openmp.md
    59 data-science/dl-frameworks/running-pytorch-conda.md
    59 data-science/dl-frameworks/running-tensorflow-conda.md
    65 data-science/building-python-packages.md
    69 applications-and-libraries/applications/gromacs.md
    71 programming-models/raja.md
   149 data-science/dl-frameworks/distributed-training-using-data-parallelism.md
   156 data-science/dl-frameworks/deepspeed.md
   186 compiling-and-linking/continuous-integration.md
   287 data-science/containers/containers.md
   432 queueing-and-running-jobs/job-and-queue-scheduling.md
   522 performance-tools/nvidia-nsight.md
  2337 total