Add doctest fixtures back

Author: stefanv

src/skimage/conftest.py

@@ -0,0 +1,15 @@
+# Fixtures for doctests
+
+import pytest
+
+
+@pytest.fixture(autouse=True)
+def handle_np2():
+    # TODO: remove when we require numpy >= 2
+    raise RuntimeError("foo")
+    try:
+        import numpy as np
+
+        np.set_printoptions(legacy="1.21")
+    except ImportError:
+        pass

src/skimage/meson.build

@@ -115,6 +115,7 @@ endif
 python_sources = [
   '__init__.py',
   '__init__.pyi',
+  'conftest.py',
   'py.typed'
 ]