code: private void updateLetsEncrypt() {
  
          getReport().println(Messages.get().container(Messages.RPT_STARTING_LETSENCRYPT_UPDATE_0));
  
          CmsLetsEncryptConfiguration config = OpenCms.getLetsEncryptConfig();
          if ((config == null) || !config.isValidAndEnabled()) {
              return;
          }
          CmsSiteConfigToLetsEncryptConfigConverter converter = new CmsSiteConfigToLetsEncryptConfigConverter(config);
          boolean ok = converter.run(getReport(), OpenCms.getSiteManager());
          if (ok) {
              getReport().println(
                  org.opencms.ui.apps.Messages.get().container(org.opencms.ui.apps.Messages.RPT_LETSENCRYPT_FINISHED_0),
                  I_CmsReport.FORMAT_OK);
          }
  
      }
docs: Updates LetsEncrypt configuration.