Fix code scanning alert no. 1: Database query built from user-control…

…led sources

Co-authored-by: Copilot Autofix powered by AI <62310815+github-advanced-security[bot]@users.noreply.github.com>

controllers/post.controller.js

@@ -78,7 +78,7 @@ if(post){
 }
 
 
-    const boardCreated = await Board.findOne({ boardTitle: req.body.boardTitle });
+    const boardCreated = await Board.findOne({ boardTitle: { $eq: req.body.boardTitle } });
     if(boardCreated){
         boardCreated.posts.push(post._id);
         await boardCreated.save();