Refine setjuncitonproperties

main.py

@@ -262,11 +262,11 @@ async def fastapi_get_junction_properties(network: str, junction: str) -> dict[s
     return get_junction(network, junction)
 
 @app.post("/setjunctionproperties/")
-async def fastapi_set_junction_properties(network: str, junction: str, props: dict[str, Any]) -> ChangeSet:
+async def fastapi_set_junction_properties(network: str, junction: str, req: Request) -> ChangeSet:
+    props = await req.json()
     ps = { 'id' : junction } | props
     return set_junction(network, ChangeSet(ps))
 
-
 ############################################################
 # reservoir 3.[RESERVOIRS]
 ############################################################