Ensure tests are available in sdist (#14746)

This restores the `tests` folder for the built `sdist` tarball.

Author: Carreau

MANIFEST.in

@@ -9,8 +9,10 @@ include .flake8
 include .pre-commit-config.yaml
 include long_description.rst
 
+recursive-include tests *
+
 recursive-exclude tools *
-recursive-exclude tests *
+
 exclude tools
 exclude CONTRIBUTING.md
 exclude .editorconfig

pyproject.toml

@@ -371,7 +371,8 @@ license-files = ["LICENSE"]
 include-package-data = false
 
 [tool.setuptools.packages.find]
-exclude = ["setupext"]
+include = ["IPython*"]
+exclude = ["setupext", "tests*"]
 namespaces = false
 
 [tool.setuptools.package-data]