code: public static void assureServerExist(final Server server, final String serverId) throws MojoExecutionException {
          if (server == null) {
              throw new MojoExecutionException(String.format("Server not found in settings.xml. ServerId=%s", serverId));
          }
      }
docs: Assure the server with specified id does exist in settings.xml.
  It could be the server used for azure authentication.
  Or, the server used for docker hub authentication of runtime configuration.
  @param server
  @param serverId
  @throws MojoExecutionException