Write two functions:
The resulting array should be sorted in lexicographic ascending order (same order as a dictionary).
getVowelSubstrings("apple")
➞ ["a", "apple", "e"]
getVowelSubstrings("hmm") ➞ []
getConsonantSubstrings("aviation")
➞ ["n", "t", "tion", "v", "viat", "viation"]
getConsonantSubstrings("motor")
➞ ["m", "mot", "motor", "r", "t", "tor"]