relax numpy constraints

Author: normanrz

python/requirements.txt

@@ -1,3 +1,2 @@
 cffi
-numpy>=1.15,==1.*
-numpy<1.22; python_version < '3.8'
+numpy>=1.15

python/setup.py

@@ -88,11 +88,6 @@ def run(self):
     packages=find_packages(),
     include_package_data=True,
     license="MIT",
-    install_requires=["cffi", "numpy>=1.15,==1.*"],
-    extras_require={
-        ':python_version < "3.8"': [
-            "numpy<1.22",
-        ],
-    },
+    install_requires=["cffi", "numpy>=1.15"],
     cmdclass={"build_py": BuildPyCommand},
 )