Changed the repository for pushing the docker image to GHCR from `ghcr.io/cp6/my-idlers` to `ghcr.io/hra42/my-idlers-arm64` in order to align with the updated repository naming convention.
This commit updates the tags in the GitHub Actions workflow for building Docker images. The previous tags `ghcr.io/cp6/my-idlers` are replaced with `ghcr.io/hra42/my-idlers-arm64`. This change ensures that the correct tags are used for the Docker image.