Revert "Make job registration with labels optional"
Revert "Make job registration with labels optional"

This reverts commit aad4917fcee215572401f9b2aa664974f5cbdc19.

We ended up not using this.

Change-Id: I17d37627528ece1880d05e372099e9d1158e1fec

gooddata/zuul,gooddata/zuul,gooddata/zuul,wikimedia/integration-zuul,wikimedia/integration-zuul,wikimedia/integration-zuul,wikimedia/integration-zuul,gooddata/zuul,gooddata/zuul