Update postgresql.md

[singlebeam]

What

What is the reason for this change?

Why

Why is this change important?

How

How was this change accomplished?

Scope

• [ ] significant change to core configuration
• [ ] independent bonus guide
• [ ] simple bug fix

Fixes # (link issue)

Test & maintenance

How can the changes be tested? Is there ongoing maintenance effort? If this is a bonus guide: are you willing to update it from time to time?

Animated GIF (optional)

Add some snazz if you feel like it :)

[twofaktor]

Incorrect modification, \q is if you are inside of psql, at no time do you enter psql

Thank you for your contribution, closing this PR

[singlebeam]

Aye - sorry!