Why nerfing Brigitte's rally but not shield bash

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They are nerfing shield bash though.

Not enough nerfs to Brigitte

There is another change coming to PTR that didn’t make the first build up there. We’re raising the CD on her bash by 20% (5s->6s). We’ll keep an eye on her to make sure she is still in a good place, as the last thing we want to do is over nerf her.