Adds postgres healthcheck for local development

I misremembered from other projects and thought postgres also has healthchecks which the main community solution could depend on, but it didn't.

This MR adds the healthcheck dependency to the community-solutions service so that it starts up only after minio and postgres is accessible.

Noticed the minio depends-on doesn't even use the healthcheck, so updated both while already at it.

@takanoy does this change work for you locally?