Add regression test for figure lazy import

Author: cvanelteren

ultraplot/tests/test_imports.py

@@ -120,6 +120,14 @@ def test_optional_module_attrs():
         getattr(uplt, "pytest_plugins")
 
 
+def test_figure_submodule_does_not_clobber_callable():
+    import ultraplot as uplt
+    import ultraplot.figure as figmod
+
+    assert callable(uplt.figure)
+    assert figmod.Figure is uplt.Figure
+
+
 def test_internals_lazy_attrs():
     from ultraplot import internals