[COMMON] Fix ${p//pat/str} bashism

pointed out by checkbashisms

Issue-ID: OOM-2643
Signed-off-by: Guillaume Lambert <guillaume.lambert@orange.com>
Change-Id: Ic3162f08f39026bf15a2c5a990b0078635c1c918
diff --git a/kubernetes/portal/components/portal-mariadb/resources/config/mariadb/docker-entrypoint.sh b/kubernetes/portal/components/portal-mariadb/resources/config/mariadb/docker-entrypoint.sh
index b416fdd..0247ad6 100644
--- a/kubernetes/portal/components/portal-mariadb/resources/config/mariadb/docker-entrypoint.sh
+++ b/kubernetes/portal/components/portal-mariadb/resources/config/mariadb/docker-entrypoint.sh
@@ -278,10 +278,10 @@
 
 		if [ -n "$MYSQL_DATABASE" ]; then
 			mysql_note "Giving user ${MYSQL_USER} access to schema ${MYSQL_DATABASE}"
-			echo "GRANT ALL ON \`${MYSQL_DATABASE//_/\\_}\`.* TO '$MYSQL_USER'@'%' ;" |docker_process_sql --database=mysql
+			echo "GRANT ALL ON \`$(echo $MYSQL_DATABASE | sed 's@_@\\_@g')\`.* TO '$MYSQL_USER'@'%' ;" | docker_process_sql --database=mysql
 		fi
 
-		echo "FLUSH PRIVILEGES ;" |docker_process_sql --database=mysql
+		echo "FLUSH PRIVILEGES ;" | docker_process_sql --database=mysql
 	fi
 }