Fix "Run in Colab" and "Download Notebook" links in tutorials

[kurtamohler]

Description

Fixes the links to run tutorials in Colab and to download notebooks.

Motivation and Context

close #2134

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• Checkout action fails due to incompatible GLIBC

❌ 3 New Failures, 11 Pending, 5 Unrelated Failures

As of commit 9b38cf6 with merge base ba6897d ():

NEW FAILURES - The following jobs have failed:

• Continuous Benchmark (PR) / GPU Pytest benchmark (gh)
  Workflow failed! Resource not accessible by integration
• Habitat Tests on Linux / tests (3.9, 12.1) / linux-job (gh)
  RuntimeError: Command docker exec -t 934c2a462827d233e76ffbe82f3d684be6b0c18249b718d5edea2696f46f7c58 /exec failed with exit code 139
• RLHF Tests on Linux / unittests (3.9, 12.1) / linux-job (gh)
  RuntimeError: vmap: It looks like you're attempting to use a Tensor in some data-dependent control flow. We don't support that yet, please shout over at https://github.com/pytorch/functorch/issues/257 .

FLAKY - The following jobs failed but were likely due to flakiness present on trunk:

• Continuous Benchmark (PR) / CPU Pytest benchmark (gh) (detected as infra flaky with no log or failing log classifier)
• [Wheels / build-wheel-linux (3.10, cp310-cp310, --index-url https://download.pytorch.org/whl/cpu, "'cpu', ... (gh) (similar failure)
• [Wheels / build-wheel-linux (3.11, cp311-cp311, --index-url https://download.pytorch.org/whl/cpu, "'cpu', ... (gh) (similar failure)
• [Wheels / build-wheel-linux (3.8, cp38-cp38, --index-url https://download.pytorch.org/whl/cpu, "'cpu', '11... (gh) (similar failure)
• [Wheels / build-wheel-linux (3.9, cp39-cp39, --index-url https://download.pytorch.org/whl/cpu, "'cpu', '11... (gh) (similar failure)

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[kurtamohler]

The issue was that the ".reference.download" selects both the .py and .ipynb links, and the .ipynb one happens to appear first in the html that sphinx-gallery generates. But I'm not sure what determines the order of the links--maybe it could change between different versions of sphinx-gallery.

We could potentially do something like this instead:
$(".sphx-glr-download-jupyter").find(".download.reference")[0].href

That would only select the .ipynb, so the order of the links in the generated html wouldn't matter. However, I don't see anything about the "sphx-glr-download-jupyter" html class in the sphinx-gallery docs, so it could be unsafe to assume that that will always work. But then again, I don't know if the "download" and "reference" classes are meant for public use either.

I'm not sure what the sphinx-gallery docs say about how this is supposed to be done. I looked and was unable to find anything

[kurtamohler]

Ah, there is an issue/PR in sphinx-gallery where "sphx-glr-download-jupyter" was added for public use: sphinx-gallery/sphinx-gallery#622

So it seems like it should be safe to use it. I'll update this PR

[vmoens]

Victory!! Thanks a million