remove bracket from regex

src/index.js

@@ -159,7 +159,7 @@ const preparePreview = async function(ctx) {
   // This matches for @string followed by a space or other punctuations like ! , or .
   // The idea here is to match a plain @name but not [@name](...)
   // also: re.exec is stateful => regex is consumed and thus needs to be re-instantiated for each call
-  const rex = /(?!\[)@([a-zA-Z0-9-]+)([\s\.,!?)\]~]{1}|$)/g
+  const rex = /(?!\[)@([a-zA-Z0-9-]+)([\s\.,!?)~]{1}|$)/g
   //                                  ^ sentence ^
   //                                   delimiters