Add GH check to staged-recipes commits linking to conversion log

[jakirkham]

Recently staged-recipes feedstock conversion was migrated to admin-requests ( #542 ). As a result of this it is no longer possible to see on staged-recipes why a particular conversion failed since the status is not updated there. It would be helpful to have the status check on staged-recipes updated to link to jobs run here for conversion to make it easier to understand what went wrong when diagnosing issues.