Coveralls fail on coverage drop threshold hit on Github

[alessiolapenna]

Hi there,
we're using slather in our Github flow to send the coverage to Coveralls and it's all working fine, but we are having trouble finding a way to have the "slather action" fail if the Coverage drops under what is defined on the Coveralls repository setting.
Coveralls allows to specify a minimum threshold drop per pull request that should be respected but it doesn't seems to affect slather.
Is this possible to achieve?