chore(deps): update postgres docker tag to v15

.github/workflows/build-postgresql.yml

@@ -10,7 +10,7 @@ jobs:
 
     services:
         postgresql:
-            image: postgres:13.9
+            image: postgres:15.1
             ports:
                 - 5432:5432
             env:

docker-compose-postgresql.yml

@@ -21,7 +21,7 @@ version: '3.7'
 services:
   # Backend service
   fineractpostgresql:
-    image: postgres:14.6
+    image: postgres:15.1
     volumes:
       - ./fineract-db/docker/postgresql:/docker-entrypoint-initdb.d/:Z,ro
     restart: always