fix(setup): Fix rdflib to be >= 5.0.0 and < 6.0.0 since CubicWeb has this dependency

setup.py

@@ -16,7 +16,7 @@
 requires = {
     "cubicweb": ">=3.30",
     "yams": None,
-    "rdflib": None,
+    "rdflib": ">=5.0.0, <6.0.0",
     "Jinja2": None,
 }
 install_requires = ["{0} {1}".format(d, v or "").strip() for d, v in requires.items()]