Avoid a Sphinx that doesn't work with pyo3 (#1248)

Author: alex

setup.py

@@ -96,6 +96,9 @@ def find_meta(meta):
         ],
         extras_require={
             "test": ["flaky", "pretend", "pytest>=3.0.1"],
-            "docs": ["sphinx!=5.2.0,!=5.2.0.post0", "sphinx_rtd_theme"],
+            "docs": [
+                "sphinx!=5.2.0,!=5.2.0.post0,!=7.2.5",
+                "sphinx_rtd_theme",
+            ],
         },
     )