[bug] when project name has dashes, db-application-user isnt correctly created

[davidcheung]

reason: the script made an assumption projectName and DB_NAME is the same, which isn't the case

because dashes get stripped out from the DB_NAME, the query --query "DBInstances[?DBName=='$PROJECT_NAME'] breaks when name includes dashes
https://github.com/commitdev/zero-deployable-backend/blob/master/db-ops/create-db-user.sh#L6

problems:

• DB_ENDPOINT becomes null from the query in shell script
• DBNAME is also needed to connect to db in the kube deployment manifest
• .sql file also needs the DB_NAME i believe