Update git submodules
Update git submodules

* Update scripts/i18n from branch 'master'
  to d2cb01208e89de1d5b494c716927f141d25d46dc
  - [cleanup] rename PYWIKIBOT2_* environment variables to PYWIKIBOT_*
    
    see 870729281754
    
    Bug: T184674
    Change-Id: I2e5ad1c106ba6e4121cac0ea5f1cc8e84223f052
    
wikimedia/pywikibot-core,PersianWikipedia/pywikibot-core,wikimedia/pywikibot-core