In order to have a dedicate chat room for tree issues with a high signal to noise ratio, we've separated out a new `tree-gardener` channel from the `tree-status` channel on Discord. This updates the gardener docs to reference the new human-centric tree-gardener chat.
I've removed the line suggesting that people avoid spamming the room with requests for "when will this be resolved?" and "can I get an update?" since the doc is aimed mostly at the gardener themself and and not likely being read by those on chat asking "when will the tree be fixed?" Recently this hasn't been a source of noise.