Update babylon-testnet symbol

Author: Kwonhyukjoon

Diff for: chain/babylon-testnet/assets_2.json

@@ -3,7 +3,7 @@
         "type": "native",
         "denom": "ubbn",
         "name" : "Babylon Testnet",
-        "symbol": "BBN",
+        "symbol": "tBABY",
         "description": "Babylon Testnet Staking Coin",
         "decimals": 6,
         "image": "https://raw.githubusercontent.com/cosmostation/chainlist/master/chain/babylon-testnet/asset/bbn.png",

Diff for: chain/babylon-testnet/param_2.json

@@ -3,7 +3,7 @@
     "chain_name": "Babylon Testnet",
     "chain_image": "https://raw.githubusercontent.com/cosmostation/chainlist/master/chain/babylon-testnet/resource/chain_babylon-testnet.png",
     "main_asset_denom" : "ubbn",
-    "main_asset_symbol": "BBN",
+    "main_asset_symbol": "tBABY",
     "main_asset_image": "https://raw.githubusercontent.com/cosmostation/chainlist/master/chain/babylon-testnet/asset/bbn.png",
     "is_support_mobile_wallet" : true,
     "is_support_extension_wallet" : true,