bump MariaDB version

EOL for 11.2 is coming up in a few weeks, see: https://mariadb.org/about/#maintenance-policy

I upgraded my local MariaDB dev database to 11.4 and performed a few cursory GETs and PUTs via the Fineract API--just what I've learned to do so far. Nothing broke. I didn't run all the tests though.

I didn't see any obvious red flags in https://mariadb.com/kb/en/changes-improvements-in-mariadb-11-4/

config/docker/compose/mariadb.yml

@@ -18,7 +18,7 @@ version: "3.8"
 services:
   mariadb:
     container_name: mariadb
-    image: mariadb:11.2
+    image: mariadb:11.4
     volumes:
       - ${PWD}/config/docker/mysql/conf.d/server_collation.cnf:/etc/mysql/conf.d/server_collation.cnf:ro
       - ${PWD}/config/docker/mysql/docker-entrypoint-initdb.d:/docker-entrypoint-initdb.d:Z,ro