chore: make the bump-script work again
chore: make the bump-script work again

no feature parity yet. still feels more automated as it does CHANGES.md by
itself. (which might be a bad thing when not paying close attention to what
exactly is changed. let's see in the future how that turns out.)

dcos/dcos-ui,dcos/dcos-ui,dcos/dcos-ui,dcos/dcos-ui,dcos/dcos-ui