Updated PSQL entrypoint in docker-compose.yml

[cduverne]

When running make docker-compose after a fresh clone, it's complaining about duplicate entries in docker-compose.yml.

This solved the issue.

What do you think ?

[ghost]

It looks like @cduverne hasn't signed our Contributor License Agreement, yet.

Appreciation of efforts,

clabot

[CLAassistant]

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