Sync simple-linked-list docs with problem-specifications

[kytrinyx]

The simple-linked-list exercise has been overhauled as part of a project to make practice exercises more consistent and friendly.

For more context, please see the discussion in the forum, as well as the pull request that updated the exercise in the problem-specifications repository:

• https://forum.exercism.org/t/new-project-making-practice-exercises-more-consistent-and-human-across-exercism/3943

Related: exercism/problem-specifications#2244

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If you approve this pull request, I will eventually merge it. However, if you are happy with this change please merge the pull request, as it will get the changes into the hands of the students much more quickly.

If this pull request contradicts the exercise on your track, please add a review with request changes. This will block the pull request from getting merged.

Otherwise, as discussed in the forum post linked to above, we aim to take an optimistic merging approach.

If you wish to suggest tweaks to these changes, please open a pull request to the exercism/problem-specifications repository to discuss, so that everyone who has an interest in the shared exercise descriptions can participate.

[github-actions]

Thank you for contributing to exercism/elixir 💜 🎉. This is an automated PR comment 🤖 for the maintainers of this repository that helps with the PR review process. You can safely ignore it and wait for a maintainer to review your changes.

Based on the files changed in this PR, it would be good to pay attention to the following details when reviewing the PR:

• General steps

  • 🏆 Does this PR need to receive a label with a reputation modifier (x:size/{tiny,small,medium,large,massive})? (A medium reputation amount is awarded by default, see docs)

• Any exercise changed

  • 👤 Does the author of the PR need to be added as an author or contributor in <exercise>/.meta/config.json (see docs)?
  • 🔬 Do the analyzer and the analyzer comments exist for this exercise? Do they need to be changed?
  • 📜 Does the design file (<exercise>/.meta/design.md) need to be updated to document new implementation decisions?

• Practice exercise changed

  • 🌲 Do prerequisites, practices, and difficulty in config.json need to be updated?
  • 🧑‍🏫 Are the changes in accordance with the community-wide problem specifiations?

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Automated comment created by PR Commenter 🤖.