python3Packages.kmapper: add missing test dependency

Changed files
+2
pkgs
development
python-modules
kmapper
+2
pkgs/development/python-modules/kmapper/default.nix
···
scipy,
# tests
+
anywidget,
igraph,
ipywidgets,
matplotlib,
···
pythonImportsCheck = [ "kmapper" ];
nativeCheckInputs = [
+
anywidget
igraph
ipywidgets
matplotlib