Added test_24h_price_change.py

Author: Trivium0911

integration_tests/rest/test_24h_price_change.py

@@ -0,0 +1,21 @@
+class Test24hPriceChange:
+
+    def test_response_corresponds_swagger_schema(self, client):
+        resp_keys = [
+            'symbol', 'priceChange', 'priceChangePercent',
+            'weightedAvgPrice', 'prevClosePrice', 'lastPrice',
+            'lastQty', 'bidPrice', 'askPrice',
+            'openPrice', 'highPrice', 'lowPrice',
+            'volume', 'quoteVolume', 'openTime', 'closeTime'
+        ]
+        price_changes = client.get_24h_price_change('GBP/USD_LEVERAGE')
+        assert type(price_changes) is dict
+        assert len(price_changes) > 0
+        assert all(dct in resp_keys for dct in price_changes.keys())
+        assert all(price_changes[key] is not None for key in
+                   price_changes.keys())
+
+    def test_wrong_symbol(self, client):
+        price_changes = client.get_24h_price_change(symbol="TEST123")
+        assert price_changes['code'] == -1128 and 'symbol not found ' \
+               in price_changes['msg']