minor #14434 Update doctrine.rts (LeorentKelmendi)

This PR was submitted for the 5.1 branch but it was merged into the 4.4 branch instead.

Discussion
----------

Update doctrine.rts

Query example in documentation has a missing `;`

<!--

If your pull request fixes a BUG, use the oldest maintained branch that contains
the bug (see https://symfony.com/releases for the list of maintained branches).

If your pull request documents a NEW FEATURE, use the same Symfony branch where
the feature was introduced (and `5.x` for features of unreleased versions).

-->

Commits
-------

7e1d00d Update doctrine.rts

Author: javiereguiluz

doctrine.rst

@@ -780,7 +780,7 @@ based on PHP conditions)::
             ->orderBy('p.price', 'ASC');
 
         if (!$includeUnavailableProducts) {
-            $qb->andWhere('p.available = TRUE')
+            $qb->andWhere('p.available = TRUE');
         }
 
         $query = $qb->getQuery();