From: Michael R. Crusoe <crusoe@debian.org>
Subject: explictly include non-Python files for those building from sdist
Forwarded: https://github.com/galaxyproject/galaxy/pull/23988

and therefore they are not tracked by any VCS

https://setuptools.pypa.io/en/latest/userguide/datafiles.html#include-package-data

--- /dev/null
+++ python-galaxy-util/MANIFEST.in
@@ -0,0 +1,3 @@
+include src/galaxy/util/rules_dsl_spec.yml
+include src/galaxy/util/docutils_template.txt
+include src/galaxy/exceptions/error_codes.json
