Update mailer.rst

HeahDude · feymo · web-flow · commit c3584a9c7ce2 · 2023-08-19T11:12:24.000+02:00
Co-authored-by: Félix Eymonot &lt;60115888+feymo@users.noreply.github.com&gt;
diff --git a/mailer.rst b/mailer.rst
@@ -576,7 +576,7 @@ the ``DataPart``::
 .. deprecated:: 6.2
 
     In Symfony versions previous to 6.2, the method ``attachPart()`` could be
-    used to add attachments. These methods have been deprecated and replaced
+    used to add attachments. This method has been deprecated and replaced
     with ``addPart()``.
 
 Embedding Images
