Add OS classifiers to .toml file

Author: andreArtelt

pyproject.toml

@@ -13,6 +13,9 @@ requires-python = ">=3.10"
 classifiers = [
     "Development Status :: 4 - Beta",
     "Intended Audience :: Science/Research",
+    "Operating System :: Microsoft :: Windows",
+    "Operating System :: MacOS",
+    "Operating System :: POSIX :: Linux",
     "Programming Language :: Python :: 3",
     "Programming Language :: Python :: 3.10",
     "Programming Language :: Python :: 3.11",