Remove Cython 3 restriction

pyproject.toml

@@ -1,7 +1,7 @@
 [build-system]
 requires = [
     "setuptools",
-    "cython>=0.25,<3.0",
+    "cython>=0.25",
     "cymem>=2.0.2,<2.1.0",
     "preshed>=3.0.2,<3.1.0",
     "murmurhash>=0.28.0,<1.1.0",

requirements.txt

@@ -23,7 +23,7 @@ setuptools
 packaging>=20.0
 # Development dependencies
 pre-commit>=2.13.0
-cython>=0.25,<3.0
+cython>=0.25
 pytest>=5.2.0,!=7.1.0
 pytest-timeout>=1.3.0,<2.0.0
 mock>=2.0.0,<3.0.0

setup.cfg

@@ -34,7 +34,7 @@ python_requires = >=3.9,<3.13
 # NOTE: This section is superseded by pyproject.toml and will be removed in
 # spaCy v4
 setup_requires =
-    cython>=0.25,<3.0
+    cython>=0.25
     numpy>=2.0.0,<3.0.0; python_version < "3.9"
     numpy>=2.0.0,<3.0.0; python_version >= "3.9"
     # We also need our Cython packages here to compile against