add missing dependency on elephant

packages/wf-multi-area-model/package.py

@@ -26,6 +26,7 @@ class WfMultiAreaModel(Package):
     depends_on("py-future", type=("run", "test"))
     depends_on("nest", type=("run", "test"))
     depends_on("py-neo", type=("run", "test"))
+    depends_on("py-elephant", type=("run", "test"))
     depends_on("r-aod", type=("run", "test"))
     depends_on("py-notebook", type=("run", "test"))