it seems like name conflict can you just rename to something different than test-mlflow.

You can also try to clean directories if there is nothing important (but I am not sure is/ adb on dbfs storage):

dbutils.fs.rm("/databricks/mlflow-tracking/1823487114958629", recurse=True)
dbutils.fs.rm("/adb/6432554542138879/1823487114958629/learning/Mlflow-Full-Example/test-mlflow", recurse=True)