Update osa6c.md

initalState, -> initalState: []
initialState should be now initialState: [],
as guided before.

Author: lnxbusdrvr

src/content/6/fi/osa6c.md

@@ -153,7 +153,7 @@ Monen actionin dispatchaaminen vaikuttaa hieman epäkäytännölliseltä. Lisät
 
 const noteSlice = createSlice({
   name: 'notes',
-  initialState,
+  initialState: [],
   reducers: {
     createNote(state, action) {
       const content = action.payload