Fixed small bug in ServeArticle where it was looking at the link to read the file

cmd/calls/articles.go

@@ -35,7 +35,8 @@ func ServeArticle(c *b.Config, db *b.DB) http.HandlerFunc {
 			return
 		}
 
-		contentBytes, err := os.ReadFile(article.Link)
+		articleAbsName := fmt.Sprint(c.ArticleDir, "/", article.ID, ".md")
+		contentBytes, err := os.ReadFile(articleAbsName)
 		if err != nil {
 			log.Println(err)
 			http.Error(w, err.Error(), http.StatusInternalServerError)