fix: proper LICENSE metadata for package (#893)

Author: RobPasMue

pyproject.toml

@@ -9,7 +9,8 @@ version = "0.10.1.dev0"
 description = "PyDPF-Post Python library."
 readme = "README.md"
 requires-python = ">=3.9,<4.0"
-license = {file = "LICENSE"}
+license = "MIT"
+license-files = ["LICENSE"]
 authors = [
     {name = "ANSYS, Inc.", email = "[email protected]"},
 ]