Workaround: trigger transitionend manually

[shgeum]

When activeFilter and targetFilter were the same, there was an issue where the transition did not occur and the event of transitionend was not triggered, resulting in a huge amount of blank space when scrolling inside with max-height specified and overflow-y: scroll.

This happened because
filterItems.styles.resetDisplay(); : Filterizr.ts:211
Afterwards, any items that were display:none will be visible again, but if you call
Since setHidden() is handled by the transitionend event, if the transition didn't happen, they would not be display: none again.

I've now patched it to force it to trigger the event.