[Feature]: Ensure that `Dockerfile`s have a healthcheck and a non-root user

[svrnm]

Problem Statement

The current Dockerfiles for services, databases and loaders do not have a HEALTHCHECK and a non-root user. Those are best practices as defined in CKV_DOCKER_2, CKV_DOCKER_3, see https://www.checkov.io/5.Policy%20Index/dockerfile.html

Proposed Solution

Fix all existing dockerfiles and also make sure that future dockerfiles follow this best practice

Alternatives Considered

No response

Additional Context

No response

Checklist

• I have read the contributing guidelines
• I have verified this does not duplicate an existing feature request