Simplify one-line docstrings for snippets

[deppen8]

Closes #291

This PR removes the * from the triple-quoted docstrings in some of the code snippets. This should hopefully make them look more like the Python standards set it PEP 257 that learners are likely encounter outside the lesson.

The PR also removes some extra blank lines that my Markdown linter didn't like.

[github-actions]

Thank you!

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🤖 This automated message can help you check the rendered files in your submission for clarity. If you have any questions, please feel free to open an issue in {sandpaper}.

If you have files that automatically render output (e.g. R Markdown), then you should check for the following:

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Rendered Changes

🔍 Inspect the changes: https://github.com/datacarpentry/image-processing/compare/md-outputs..md-outputs-PR-293

The following changes were observed in the rendered markdown documents:

 02-image-basics.md   | 16 +++++-----------
 03-skimage-images.md | 45 +++++++--------------------------------------
 edge-detection.md    | 31 +++++++++----------------------
 md5sum.txt           |  6 +++---
 4 files changed, 24 insertions(+), 74 deletions(-)

What does this mean?

If you have source files that require output and figures to be generated (e.g. R Markdown), then it is important to make sure the generated figures and output are reproducible.

This output provides a way for you to inspect the output in a diff-friendly manner so that it's easy to see the changes that occur due to new software versions or randomisation.

⏱️ Updated at 2023-08-16 02:50:49 +0000

[tobyhodges]

Looks good to me. Thanks, @deppen8. I have suggested only one change, to fix a typo that went undetected until now.

[deppen8]

I have suggested only one change, to fix a typo that went undetected until now.

Ha! How did I miss that while editing that exact line? Done.