Use spoilers instead of floating solutions

[tobyhodges]

This PR introduces spoiler divs to the lesson, in place of "floating" solution blocks that are not associated with a challenge block. I think this will look better in the built lesson than the current solution blocks, which are positioned suboptimally when not adjoining a challenge.

[github-actions[bot]]

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:robot: 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:

• :dart: correct output
• :framed_picture: correct figures
• :question: new warnings
• :bangbang: new errors

Rendered Changes

:mag: Inspect the changes: https://github.com/carpentries-incubator/managing-computational-projects/compare/md-outputs..md-outputs-PR-117

The following changes were observed in the rendered markdown documents:

 21_Definitions.md                |  5 ++++-
 22_contentAndMotivation.md       |  2 +-
 24_SettingUp.md                  |  6 ++++--
 26_Coding.md                     |  2 +-
 files/01-introduction.md         |  5 ++++-
 files/02-motivation.md           |  2 +-
 files/08-collaborativeworking.md |  2 +-
 files/13-codereview.md           |  2 +-
 md5sum.txt                       | 14 +++++++-------
 9 files changed, 24 insertions(+), 16 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.

:stopwatch: Updated at 2023-09-06 19:35:41 +0000

[malvikasharan]

Thank you so much Toby! 🥇 @jcolomb @johav Tagging for your awareness.