fix(currency-slice): use new constant

src/redux/Currency/slice.ts

@@ -1,12 +1,9 @@
 import { createSlice } from '@reduxjs/toolkit'
-
-import { CURRENCIES } from '../../constants'
-
-export type CurrencyType = keyof typeof CURRENCIES
+import { INITIAL_CURRENCY } from '../../constants'
 
 const currencySlice = createSlice({
   name: 'currency',
-  initialState: Object.keys(CURRENCIES)[0],
+  initialState: INITIAL_CURRENCY,
   reducers: {
     setCurrency: (_, action) => {
       return action.payload