Move project metadata to pyproject.toml (jaraco/skeleton#122)

Intentionally omitted specifying `tool.setuptools.include-package-data`: it's true by default in `pyproject.toml` according to https://setuptools.pypa.io/en/latest/userguide/datafiles.html#include-package-data.

Closes jaraco/skeleton#121

pyproject.toml

@@ -1,5 +1,52 @@
 [build-system]
-requires = ["setuptools>=56", "setuptools_scm[toml]>=3.4.1"]
+requires = ["setuptools>=61.2", "setuptools_scm[toml]>=3.4.1"]
 build-backend = "setuptools.build_meta"
 
+[project]
+name = "PROJECT"
+authors = [
+	{ name = "Jason R. Coombs", email = "[email protected]" },
+]
+description = "PROJECT_DESCRIPTION"
+readme = "README.rst"
+classifiers = [
+	"Development Status :: 5 - Production/Stable",
+	"Intended Audience :: Developers",
+	"License :: OSI Approved :: MIT License",
+	"Programming Language :: Python :: 3",
+	"Programming Language :: Python :: 3 :: Only",
+]
+requires-python = ">=3.8"
+dependencies = [
+]
+dynamic = ["version"]
+
+[project.optional-dependencies]
+testing = [
+	# upstream
+	"pytest >= 6, != 8.1.*",
+	"pytest-checkdocs >= 2.4",
+	"pytest-cov",
+	"pytest-mypy",
+	"pytest-enabler >= 2.2",
+	"pytest-ruff >= 0.2.1",
+
+	# local
+]
+docs = [
+	# upstream
+	"sphinx >= 3.5",
+	"jaraco.packaging >= 9.3",
+	"rst.linker >= 1.9",
+	"furo",
+	"sphinx-lint",
+
+	# local
+]
+
+[project.urls]
+Homepage = "https://github.com/PROJECT_PATH"
+
+[project.scripts]
+
 [tool.setuptools_scm]