Add possibility to customize choose Postgres Database Image

[raideno]

Is your feature request related to a problem? Please describe.
Currently, the Postgres database image used weighs nearly 3GB, which might be too heavy for some systems, especially if used only for development.

Describe the solution you'd like
Provide the possibility to manually set the name of the database image in the config.toml file, allowing users to choose a lighter alpine version.

Describe alternatives you've considered
Make it possible to specify the image name via the CLI.

Additional context
Add any other context or screenshots about the feature request here.