Update docs/configuring-playbook-email.md: minor edit

Signed-off-by: Suguru Hirahara <acioustick@noreply.codeberg.org>

docs/configuring-playbook-email.md

@@ -31,7 +31,7 @@ By default, exim-relay attempts to deliver emails directly. This may or may not
 
 To improve email deliverability, you can configure authentication methods such as DKIM (DomainKeys Identified Mail), SPF, and DMARC for your domain. Without setting any of these authentication methods, your outgoing email is most likely to be quarantined as spam at recipient's mail servers.
 
-For details about configuring DKIM, refer [this section](https://github.com/mother-of-all-self-hosting/ansible-role-exim-relay/blob/main/docs/configuring-exim-relay.md#enable-dkim-support-optional) on the role's document.
+For details about configuring DKIM, refer [this section](https://github.com/mother-of-all-self-hosting/ansible-role-exim-relay/blob/main/docs/configuring-exim-relay.md#enable-dkim-support-optional) on the role's documentation.
 
 💡 If you cannot enable DKIM, SPF, or DMARC on your domain for some reason, we recommend relaying email through another SMTP server.