Fix classifiers in metadata

README.md

@@ -1,6 +1,6 @@
 # Grid
 
-[![Python Version](https://img.shields.io/badge/python-3.7%2B-blue.svg)](https://docs.python.org/3/whatsnew/3.7.html)
+[![Python Version](https://img.shields.io/badge/python-3.9%2B-blue.svg)](https://docs.python.org/3/whatsnew/3.9.html)
 [![GPLv3 License](https://img.shields.io/badge/License-GPL%20v3-yellow.svg)](https://opensource.org/licenses/)
 [![GitHub Actions CI Tox Status](https://github.com/theochem/grid/actions/workflows/pytest.yaml/badge.svg)](https://github.com/theochem/grid/actions/workflows/pytest.yaml)
 [![GitHub contributors](https://img.shields.io/github/contributors/theochem/grid.svg)](https://github.com/theochem/grid/graphs/contributors)

pyproject.toml

@@ -10,9 +10,9 @@ authors = [
 description = "Grid performs numerical integration, interpolation and differentiation."
 readme = "README.md"
 license = {text = "GPL-3.0-or-later"}
-requires-python = ">=3.7"
+requires-python = ">=3.9"
 classifiers = [
-   'Development Status :: 0 - Released',
+    'Development Status :: 5 - Production/Stable',
     'Environment :: Console',
     'License :: OSI Approved :: GNU General Public License v3 or later (GPLv3+)',
     'Operating System :: POSIX :: Linux',
@@ -21,11 +21,10 @@ classifiers = [
     'Intended Audience :: Science/Research',
     "Intended Audience :: Education",
     "Natural Language :: English",
-    'Programming Language :: Python :: 3.7',
-    "Programming Language :: Python :: 3.8",
     "Programming Language :: Python :: 3.9",
     "Programming Language :: Python :: 3.10",
     "Programming Language :: Python :: 3.11",
+    "Programming Language :: Python :: 3.12",
 ]
 dependencies = [
     "numpy>=1.16",