[Stable-Only] docker: Pin postgres, mysql image versions

Signed-off-by: Stephen Finucane <stephen@that.guru>

Author: stephenfin

docker-compose-pg.yml

@@ -1,7 +1,7 @@
 ---
 services:
   db:
-    image: postgres:latest
+    image: postgres:17
     volumes:
       - ./tools/docker/db/postdata:/var/lib/postgresql/data
     environment:

docker-compose.yml

@@ -1,7 +1,7 @@
 ---
 services:
   db:
-    image: mysql:latest
+    image: mysql:8.4
     volumes:
       - ./tools/docker/db/data:/var/lib/mysql
     environment: