fix:dynamic mention options do not always load (#36)

Co-authored-by: GYL <sehun@0412.com>

Author: Gylllll

src/Mentions.tsx

@@ -189,6 +189,7 @@ class Mentions extends React.Component<MentionsProps, MentionsState> {
       if (validateMeasure) {
         if (
           key === measurePrefix ||
+          key === 'Shift'||
           measuring ||
           (measureText !== prevMeasureText && matchOption)
         ) {