Map<String, String> getEnvironment() {
    String property = getProperty(PropertyNames.CONTAINER_ENVIRONMENT);
    if (property != null) {
      return ConfigurationPropertyValidator.parseMapProperty(property);
    }
    return container.environment;
  }
Gets the configured environment variables.

@return the configured environment variables
jib-maven-plugin/src/main/java/com/google/cloud/tools/jib/maven/JibPluginConfiguration.java