[GAMEPLAY] Taric Ult Halts Various Autoattack Passive Stacking

In Taric's rework, it was made very clear that his ult, once it actually hit, would block any and all damage, but not CC. However, it seems to make it impossible to apply Braum's passive stacks (and therefore to proc the subsequent stun) with autoattacks. I also checked other autoattacks that apply stacks, and it seems like Taric ult also halts Darius passive and Vayne W. I also checked that Kayle ult---for a natural comparison---does in fact not do this (e.g. Braum autoattacking an ulted Kayle applies his stacks). However, Braum Q does apply a passive stack even on an ulted Taric.

Reproduction steps:

1. Pick Braum vs. Taric.
2. Have Taric cast his ult.
3. Wait for the ult to fall.
4. Have Braum autoattack Taric while the latter is invulnerable.

This works 100% of the time on patch 6.10.