chore(deps): pin dependencies

Change-Id: I44bb272cd38668f4ecd44ba9fe97c97cdb0b08a7
diff --git a/docker-compose.dev.yml b/docker-compose.dev.yml
index a67ce0d..b222ec4 100644
--- a/docker-compose.dev.yml
+++ b/docker-compose.dev.yml
@@ -25,7 +25,7 @@
     networks:
       - backend
   db:
-    image: mariadb
+    image: mariadb@sha256:9da6213d1a5714c4585c9c0003c51510b320d6f60e53d78701fe1e194126249f
     environment:
       MYSQL_ALLOW_EMPTY_PASSWORD: "yes"
       MARIADB_DATABASE: twpt