Cleanup not required cleanup sql script

Since we introduced migration the init file is not required and it is a
leftover.

Signed-off-by: Gianluca Arbezzano <gianarb92@gmail.com>

deploy/docker-compose.yml

@@ -65,7 +65,6 @@ services:
       POSTGRES_PASSWORD: tinkerbell
       POSTGRES_USER: tinkerbell
     volumes:
-      - ./db/tinkerbell-init.sql:/docker-entrypoint-initdb.d/tinkerbell-init.sql:ro
       - postgres_data:/var/lib/postgresql/data:rw
     ports:
       - 5432:5432