quiet takes care of both the error and success case.
Without this, there are lines like:
myzpool/vm-4352-disk-0@__replicate_4352-7_1601538554__ name myzpool/vm-4352-disk-0@__replicate_4352-7_1601538554__ -
in the log if the dataset exists, and this information is
already present in more readable form.
Signed-off-by: Fabian Ebner <f.ebner@proxmox.com>