fix: move the default query client to outside of the component (#437)

The current implementation of the query client within the function
component leads to the creation of a new query client on each re-render.
Consequently, this behavior results in the loss of data and caches
associated with the query client.

This PR addresses the issue by relocating the default query client
outside of the function component. By doing so, we ensure that the query
client persists across re-renders, maintaining data integrity and cache
consistency.

While it's possible to resolve this issue by directly providing the
query client to the Provider on usage, this caused us some time to
locate and fix the issue, hence the decision to refactor the
implementation.

.changeset/shy-planets-poke.md

@@ -0,0 +1,5 @@
+---
+"@starknet-react/core": patch
+---
+
+Move the default query client to outside of the Provider component

packages/core/src/context/starknet.tsx

@@ -17,6 +17,8 @@ import { ChainProviderFactory } from "~/providers";
 import { ExplorerFactory } from "~/explorers/";
 import { AccountProvider } from "./account";
 
+const defaultQueryClient = new QueryClient();
+
 /** State of the Starknet context. */
 export interface StarknetState {
   /** Connected connector. */
@@ -317,7 +319,7 @@ export function StarknetProvider({
   });
 
   return (
-    <QueryClientProvider client={queryClient ?? new QueryClient()}>
+    <QueryClientProvider client={queryClient ?? defaultQueryClient}>
       <StarknetContext.Provider value={state}>
         <AccountProvider account={account}>{children}</AccountProvider>
       </StarknetContext.Provider>