fix package metadata issue (#203)

pyproject.toml

@@ -8,6 +8,7 @@ maintainers = [
 ]
 readme = "README.md"
 version = "0.6.17"
+license = {text = "MIT"}
 description = "Modern datetime library for Python"
 requires-python = ">=3.9"
 classifiers = [
@@ -87,6 +88,12 @@ ignore_missing_imports = true
 [tool.setuptools.packages]
 find = { where = ["pysrc"] }
 
+[tool.setuptools]
+# FUTURE: remove this once PEP639 compatibility issue is solved
+# Note that maturin build still includes the license files in the wheel.
+# Nothing to worry about.
+license-files = []
+
 # Notes about the build configuration:
 # We need setuptools_rust to support enabling/disabling building the Rust
 # extension from source distributions.
@@ -95,6 +102,7 @@ find = { where = ["pysrc"] }
 [tool.maturin]
 python-source = "pysrc"
 module-name = "whenever._whenever"
+# include = ["LICENSE*"]
 
 [build-system]
 build-backend = "setuptools.build_meta"