fix(docker-build): start main process with exec (#1210)

* Use exec

* Appl shellcheck fixes

* Close with newline

machine-learning/entrypoint.sh

@@ -1,3 +1,4 @@
+#! /bin/sh
 # npm run typeorm migration:run
 # npm run start:prod
-node dist/main.js
+exec node dist/main.js