Use osc's devel_project implementation instead

lib/obs.py

@@ -124,11 +124,8 @@ class OBS:
         return root.get("project") == project
 
     def devel_project(self, project, package):
-        root = self._meta(f"{project}/{package}")
-        devel = root.find("devel")
-        if devel is None:
-            return None
-        return devel.get("project")
+        develprj, _ = osc.core.show_devel_project(self.url, project, package)
+        return develprj
 
     def request(self, requestid):
         root = self._request(requestid)