@Nullable
  String getBaseImage() {
    String property = getProperty(PropertyNames.FROM_IMAGE);
    if (property != null) {
      return property;
    }
    return from.image;
  }
Gets the base image reference.

@return the configured base image reference
jib-maven-plugin/src/main/java/com/google/cloud/tools/jib/maven/JibPluginConfiguration.java