fix: check null

src/status/signals/wallet.nim

@@ -9,6 +9,7 @@ proc fromEvent*(jsonSignal: JsonNode): Signal =
     signal.blockNumber = jsonSignal["event"]{"blockNumber"}.getInt
     signal.erc20 = jsonSignal["event"]{"erc20"}.getBool
     signal.accounts = @[]
+    if jsonSignal["event"]["accounts"].kind != JNull:
       for account in jsonSignal["event"]["accounts"]:
         signal.accounts.add(account.getStr)
   result = signal