build(backport): Use notebook over jupyter (#2508)

* Backport PR #2507
* jupyter is a metapackage that is never updated, so defining the
  notebook dependency provides better control on the actual tools
  required.

Co-authored-by: Matthew Feickert <matthew.feickert@cern.ch>

pyproject.toml

@@ -111,7 +111,7 @@ test = [
     "pydocstyle",
     "papermill>=2.3.4",
     "scrapbook>=0.5.0",
-    "jupyter",
+    "notebook>=6.5.7",
     "graphviz",
     "pytest-socket>=0.2.0",  # c.f. PR #1917
 ]