add support of arm64 architecture for nginx-flask-mysql

Signed-off-by: Guillaume Lours <guillaume.lours@docker.com>

nginx-flask-mysql/docker-compose.yaml

@@ -1,6 +1,9 @@
 services:
   db:
-    image: mysql:8.0.19
+    # We use a mariadb image which support both amd64 & arm64 architecture
+    image: mariadb:10.6.4-focal
+    # If you really want to use MySQL, uncomment the following line
+    #image: mysql:8.0.27
     command: '--default-authentication-plugin=mysql_native_password'
     restart: always
     healthcheck: