Raise min version of NumPy dependency.

Tcod always uses the type hinting features of the latest NumPy.

This is the final version of NumPy with Python 3.7 support.

Fixes #115

Author: HexDecimal

requirements.txt

@@ -1,5 +1,5 @@
 cffi>=1.15
-numpy>=1.20.3
+numpy>=1.21.4
 pycparser>=2.14
 setuptools==60.8.2
 types-setuptools

setup.py

@@ -120,7 +120,7 @@ def check_sdl_version() -> None:
     ],
     install_requires=[
         "cffi>=1.15",  # Also required by pyproject.toml.
-        "numpy>=1.20.3" if not is_pypy else "",
+        "numpy>=1.21.4" if not is_pypy else "",
         "typing_extensions",
     ],
     cffi_modules=["build_libtcod.py:ffi"],