canBeJungseong
Check if a given character can be a jungseong in Korean.
function canBeJungseong(character: string): boolean;Examples
canBeJungseong('ㅏ'); // true
canBeJungseong('ㅗㅏ'); // true
canBeJungseong('ㅏㅗ'); // false
canBeJungseong('ㄱ'); // false
canBeJungseong('ㄱㅅ'); // false
canBeJungseong('가'); // false