Check and update localization instructions
Following merge of https://github.com/civicrm/civicrm-core/pull/17006. Also mention https://lab.civicrm.org/extensions/kamlanguage and the CiviCRM language switcher if it makes sense.
Following merge of https://github.com/civicrm/civicrm-core/pull/17006. Also mention https://lab.civicrm.org/extensions/kamlanguage and the CiviCRM language switcher if it makes sense.