Leap 48in24 approaches fixes

[michalporeba]

This is a PR to collect all the fixes to the initial version of the Leap approaches.
It relates to #1401 and the 48in24 challenge.

Let's wait until the end of today to collect any feedback and resulting updates before merging.

[github-actions]

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

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• 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)?
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• Practice exercise changed

  • 🌲 Do prerequisites, practices, and difficulty in config.json need to be updated?
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