fix healthcheck warning (#14)

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* [x] I have deployed and tested my changes
* [x] I have [updated relevant versions in `abra.sh`](https://docs.coopcloud.tech/maintainers/upgrade/#updating-versions-in-the-abrash)
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Reviewed-on: https://git.coopcloud.tech/coop-cloud/uptime-kuma/pulls/14
Co-authored-by: stevensting <stefan@klasse-methode.it>
Co-committed-by: stevensting <stefan@klasse-methode.it>

compose.mariadb.yml

@@ -38,7 +38,7 @@ services:
         backupbot.backup.volumes.mariadb.path: "dump.sql.gz"
         backupbot.restore.post-hook: "gzip -d /var/lib/mysql/dump.sql.gz && mariadb -u root -p\"$$(cat /run/secrets/db_root_password)\" kuma < /var/lib/mysql/dump.sql && rm -f /var/lib/mysql/dump.sql"
     healthcheck:
-      test: ["CMD-SHELL", 'mariadb-admin -p"$$(cat $MYSQL_ROOT_PASSWORD_FILE)"  ping']
+      test: ["CMD-SHELL", 'mariadb-admin -u"$$MYSQL_USER" -p"$$(cat $$MYSQL_PASSWORD_FILE)" ping']
       interval: 30s
       timeout: 10s
       retries: 10