[i18n] Use additional twn messages with checkimages.py
[i18n] Use additional twn messages with checkimages.py

Bug: T220178
Change-Id: I045481ae8aee173cb513f49c1ec08d31c7d1c9d8

wikimedia/pywikibot-core,wikimedia/pywikibot-core,PersianWikipedia/pywikibot-core