Java Practice It | Exercise 10.4: doubleList | ArrayList, collections, array list

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Write a method doubleList that takes an ArrayList of Strings as a parameter and that replaces every string with two of that string. For example, if the list stores the values {"how", "are", "you?"} before the method is called, it should store the values {"how", "how", "are", "are", "you?", "you?"} after the method finishes executing.