Update script fails because dir is not mentionned in upgrade script

[ponceta]

• Fix update/upgrade_db.sh to consider delta dir

pum test-and-upgrade: error: argument -d/--dir: expected at least one argument

[ponceta]

https://github.com/qwat/qwat-data-model/blob/master/update/upgrade_db.sh#L25

Could be set by default as deltas/ or update/deltas depending on our standard update procedure and should be overwritten when specified though an env variable from the user.

Need to care for Travis / github actions needs before updating this.