[Doc] Miscellaneous changes

[peytondmurray]

Why are these changes needed?

This PR makes some miscellaneous changes needed for the docs build system upgrade:

• Fixed broken refs in the following files:
  • prometheus-grafana.md
  • rayservice-troubleshooting.md
  • troubleshooting.md
  • rayservice.md
  • data/examples/batch_training.ipynb
  • ray-overview/getting-started.md
  • ray-overview/index.md
  • ray-overview/use-cases.rst
  • serve/advanced-guides/dev-workflow.md
  • train/examples/deepspeed/gptj_deepspeed_fine_tuning.ipynb
  • train/examples/transformers/huggingface_text_classification.ipynb
  • tune/examples/batch_tuning.ipynb
• margin directives are only defined in sphinx-book-theme, so I replaced them with note directives in the following files:
  • rllib/rllib-cli.md
  • rllib/rllib-training.rst
  • serve/tutorials/rllib.md
• Added a new svg logo and CSS for the train/train.rst page. The logo dynamically adapts to dark/light theme switching. Removed old logo as a result.
• Added CSS for the ray-overview/ray-libraries page. Previously the cards on this page had their heights dynamically adjusted on each page load by a script; now this is done with CSS. The contents of this page were being generated with a custom build step using a yaml config file. Here, I've made the build more straightforward: the content in ray-overview/ray-libraries.rst is already in place.
• Fixed an issue where a code cell inside markdown in ray-contribute/docs.ipynb was being rendered poorly
• Made cards clickable links in train/more-frameworks.rst

Related issue number

Partially addresses ray-project#37944.
Depends on #2.
PR 9/x targeting ray-project#41115.

Checks

• I've signed off every commit(by using the -s flag, i.e., git commit -s) in this PR.
• I've run scripts/format.sh to lint the changes in this PR.
• I've included any doc changes needed for https://docs.ray.io/en/master/.
  • I've added any new APIs to the API Reference. For example, if I added a
    method in Tune, I've added it in doc/source/tune/api/ under the
    corresponding .rst file.
• I've made sure the tests are passing. Note that there might be a few flaky tests, see the recent failures at https://flakey-tests.ray.io/
• Testing Strategy
  • Unit tests
  • Release tests
  • This PR is not tested :(

[maxpumperla]

No issues with that one either, thank you! I really want to see the final product now. Exciting!