Performance script, available as management command

[ci skip]

docker/install_management_commands.sh

@@ -19,7 +19,8 @@ for command in decrypt_documents \
 	manage_superuser \
 	convert_mariadb_uuid \
 	prune_audit_logs \
-	createsuperuser;
+	createsuperuser \
+	document_perf_benchmark;
 do
 	echo "installing $command..."
 	sed "s/management_command/$command/g" management_script.sh >"$PWD/rootfs/usr/local/bin/$command"