Updated mediawiki/extensions
Project: mediawiki/extensions/AJAXPoll  673f0d7babcb438f356c661dd92410796966718b

Follow-up I7d4bb9062. Register tracking category used.

This allows ajaxpoll-tracking-category to appear in the newly added [[Special:TrackingCategories]].

Bug: 63283
Change-Id: I36cfa25afc8463c07b40d76ae7fe110288e1ecc3