Create a function which validates whether a 3 character string is a vowel sandwich. In order to have a valid sandwich, the string must satisfy the following rules:
isVowelSandwich("cat") ➞ true
isVowelSandwich("ear") ➞ false
isVowelSandwich("bake") ➞ false
isVowelSandwich("try") ➞ false
false if the word is not 3 characters in length.