Fix Cython version specifiers for requirements.txt

Author: cjdsellers

poetry.lock

@@ -50,7 +50,7 @@ generate-setup-file = false
 
 [tool.poetry.dependencies]
 python = ">=3.11,<3.13"
-cython = "==3.0.11 || ==3.1.0a1"  # Build dependency (pinned for stability)
+cython = ">=3.0.11,<=3.1.0a1"  # Build dependency (pinned for stability)
 numpy = ">=1.26.4,<2.2.1"  # Build dependency (unable to find 2.2.1 installation candidate?)
 setuptools = ">=75" # Build dependency
 click = "^8.1.8"