Update README.md in mlflow to match column names order (#1703)

Corrected the difference in column names in "MLflow Scoring Protocol" to match with the order in "Send test inference request". The values are in correct same order in both sections, so different columns are causing confusion.

docs/examples/mlflow/README.md

@@ -290,17 +290,17 @@ import requests
 inference_request = {
     "dataframe_split": {
         "columns": [
-            "alcohol",
-            "chlorides",
-            "citric acid",
-            "density",
             "fixed acidity",
+            "volatile acidity",
+            "citric acid",
+            "residual sugar",
+            "chlorides",
             "free sulfur dioxide",
+            "total sulfur dioxide",
+            "density",
             "pH",
-            "residual sugar",
             "sulphates",
-            "total sulfur dioxide",
-            "volatile acidity",
+            "alcohol",
         ],
         "data": [[7.4,0.7,0,1.9,0.076,11,34,0.9978,3.51,0.56,9.4]]
     }