Fix the "Transifex Zotero project page" link

yfdyh000

https://www.zotero.org/support/dev/localization page's https://www.transifex.com/projects/p/zotero/ link should be corrected as https://explore.transifex.com/zotero/zotero/ (https://www.transifex.com/zotero/zotero/).

dstillman

Fixed, thanks!