[DOC] Shapelet transform notebook

[IRKnyazev]

Reference Issues/PRs

Depends on PR #2006 - notebook uses the SAST features I added in the mentioned PR. Hence the failed notebook test.

What does this implement/fix? Explain your changes.

This notebook explores all four of aeon's transforms under the context of the GunPoint problem. I use them to drive insights into the problem while explaining and comparing the algorithms themselves too.

PR checklist

For all contributions

• [X] I've added myself to the list of contributors. Alternatively, you can use the @all-contributors bot to do this for you.
• [X] The PR title starts with either [ENH], [MNT], [DOC], [BUG], [REF], [DEP] or [GOV] indicating whether the PR topic is related to enhancement, maintenance, documentation, bugs, refactoring, deprecation or governance.