[DX] Use mailpit over mailhog

[BitcoinMitchell]

Description

Since Mailhog is two years outdated and is lacking in features, I've replaced it with Mailpit, which is inspired by Mailhog, except it is up-to-date and has a lot of extra useful features.

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Refactor (non-breaking change which improves the codebase)

How Has This Been Tested?

I've send a test email to myself using PrestaShop itself.

Test Configuration:

• PrestaShop version: 8.1.0
• PHP version: 8.1.22

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have checked my code and corrected any misspellings

[ndeet]

LGTM