public ImageFromDockerfile withDockerfile(Path dockerfile) {
        this.dockerfile = Optional.of(dockerfile);
        return this;
    }
Sets the Dockerfile to be used for this image. Honors .dockerignore files for efficiency.
Additionally, supports Dockerfiles that depend upon images from authenticated private registries.

@param dockerfile path to Dockerfile on the test host.
core/src/main/java/org/testcontainers/images/builder/ImageFromDockerfile.java