Update jupyter-book requirement from <2.0.0 to <3.0.0 (#52)

Updates the requirements on jupyter-book to permit the latest version.

---
updated-dependencies:
- dependency-name: jupyter-book
  dependency-version: 2.0.2
  dependency-type: direct:production
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

requirements.txt

@@ -1,7 +1,7 @@
 datalad
 git-annex
 imageio
-jupyter-book<2.0.0
+jupyter-book<3.0.0
 jupytext
 matplotlib
 myst_nb