fix: handle of markdownTextTs receives null

src/helpers/markdownToText.ts

@@ -1,7 +1,8 @@
 import MarkdownIt from "markdown-it";
 const parser = new MarkdownIt();
 
-export default function markdownToText(markdown: string = "<empty>"): string {
+export default function markdownToText(markdown: string): string {
+  if(!markdown) return ''
   return parser
     .render(markdown)
     .split("\n")