Add the Framework :: Sphinx :: Domain classifier

Author: AA-Turner

pyproject.toml

@@ -38,6 +38,7 @@ classifiers = [
     "Programming Language :: Python :: Implementation :: CPython",
     "Programming Language :: Python :: Implementation :: PyPy",
     "Framework :: Sphinx",
+    "Framework :: Sphinx :: Domain",
     "Framework :: Sphinx :: Extension",
     "Framework :: Sphinx :: Theme",
     "Topic :: Documentation",