fix missing var in conf.in.py
@@ -14,6 +14,7 @@ sys.path.insert(0, os.path.abspath('../../python'))
project = "qiBuild"
version = "3.13"
release = version
+extensions = list()
extensions.append("cmakedomain")
extensions.append("sphinx.ext.autodoc")
extensions.append("sphinxcontrib.spelling")
