fix: update app/src/spot_market_making/config.env.example

Author: cryptochassis

app/src/spot_market_making/config.env.example

@@ -112,15 +112,15 @@ COINBASE_API_PASSPHRASE=''
 GEMINI_API_KEY=''
 GEMINI_API_SECRET=''
 
+KRAKEN_API_KEY=''
+KRAKEN_API_SECRET=''
+
 BINANCE_API_KEY=''
 BINANCE_API_SECRET=''
 
 BINANCE_US_API_KEY=''
 BINANCE_US_API_SECRET=''
 
-HUOBI_API_KEY=''
-HUOBI_API_SECRET=''
-
 OKEX_API_KEY=''
 OKEX_API_SECRET=''
 OKEX_API_PASSPHRASE=''
@@ -139,6 +139,9 @@ FTX_US_API_KEY=''
 FTX_US_API_SECRET=''
 FTX_US_API_SUBACCOUNT=''
 
+GATEIO_API_KEY=''
+GATEIO_API_SECRET=''
+
 # end: only applicable to live trade