Fixed package discovery in pyproject.toml

pyproject.toml

@@ -40,8 +40,9 @@ requires = ["setuptools>=61.0"]
 # allow looking for conf in setup.{cfg,py}
 #build-backend = "setuptools.build_meta"
 
-[tool.setuptools]
-packages = ["borgmatic"]
+[tool.setuptools.packages.find]
+include = ["borgmatic*"]
+namespaces = false
 
 [tool.black]
 line-length = 100