Refresh Cython constraint based on upstream

msgpack/msgpack-python#581

Author: jakirkham

recipe/meta.yaml

@@ -16,13 +16,13 @@ requirements:
   build:
     - python                                 # [build_platform != target_platform]
     - cross-python_{{ target_platform }}     # [build_platform != target_platform]
-    - cython                                 # [build_platform != target_platform]
+    - cython ~=3.0.8                         # [build_platform != target_platform]
     - {{ stdlib("c") }}
     - {{ compiler("cxx") }}
   host:
     - python
     - pip
-    - cython >=0.16
+    - cython ~=3.0.8
   run:
     - python