train_test_split() error: Found input variables with inconsistent numbers of sample
Your independent variables need to be passed to the classifier's fit as a 2D array, but yours is 1D; you can use numpy's reshape: https://stackoverflow.com/questions/30813044/sklearn-found-arrays-with-inconsistent-numbers-of-samples-when-calling-linearre

Separately, I find it odd that you are trying to use quality to predict alcohol content, for which you should be using regression instead of classification.  Perhaps you meant to switch the inputs to train_test_split?