minor #11963 Change port in example MAILER_URL (thled)

This PR was merged into the 4.3 branch.

Discussion
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Change port in example MAILER_URL

The example URL for a SMTP configuration uses "encryption=ssl". Therefore it should use the SSL port for SMTP which is 465.

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Commits
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cd78ad3 Change port in example MAILER_URL

Author: javiereguiluz

email.rst

@@ -45,7 +45,7 @@ environment variable in the ``.env`` file:
     MAILER_URL=null://localhost
 
     # use this to configure a traditional SMTP server
-    MAILER_URL=smtp://localhost:25?encryption=ssl&auth_mode=login&username=&password=
+    MAILER_URL=smtp://localhost:465?encryption=ssl&auth_mode=login&username=&password=
 
 .. caution::