license update

Author: cvanelteren

pyproject.toml

@@ -20,7 +20,7 @@ maintainers = [
 description = "A succinct matplotlib wrapper for making beautiful, publication-quality graphics."
 readme = "README.rst"
 requires-python = ">=3.6.0"
-license = {text = "MIT"}
+license =  "CC-BY-SA-4.0"
 classifiers = [
     "License :: OSI Approved :: MIT License",
     "Operating System :: OS Independent",