add retry to getting tao price

app.py

@@ -68,8 +68,15 @@ class ModelData:
             emission=emission
         )
 
-def get_tao_price():
-    return float(requests.get("https://api.kucoin.com/api/v1/market/stats?symbol=TAO-USDT").json()["data"]["last"])
+def get_tao_price() -> float:
+    for i in range(0, METAGRAPH_RETRIES):
+        try:
+            return float(requests.get("https://api.kucoin.com/api/v1/market/stats?symbol=TAO-USDT").json()["data"]["last"])
+        except:
+                if i == METAGRAPH_RETRIES - 1:
+                    raise
+                time.sleep(METAGRAPH_DELAY_SECS)
+        raise RuntimeError()
 
 def print_validator_weights(metagraph: bt.metagraph):
     for uid in metagraph.uids.tolist():