Migrate off run_after_success

[simonswine]

Is this a BUG REPORT or FEATURE REQUEST?:

/kind feature

What happened:

Prow is removing support for run_after_success https://github.com/kubernetes/test-infra/pull/10694#issuecomment-453299764

What you expected to happen:

We should keep support in our fork for longer until an alternative build pipeline model is available through knative.

/cc @munnerz

[munnerz]

👋 has there been any thought as to when this might happen? I'd like to be able to bump Prow 😄

Would it be possible to get this scheduled into a milestone? I think just running all tests for all PRs initially would probably be okay, given the (relatively) low volume of jobs.

[munnerz]

(I'm happy to make the changes to move your jobs away from run_after_success and just running on all pushes, if that's a direction you're happy with - I'd just rather not block Prow bumps on this for an extended period)

[munnerz]

After discussing with @simonswine, I think a rough plan:

• At the start of the 0.7 cycle, we'll move all run_after_success jobs to run unconditionally (i.e. just absorb the cost of running more jobs)
• We can then bump Prow, and ensure all is working as expected without causing interruption
• We then have the chance to investigate and explore the knative-pipeline support that is still in the works, in our own time

Assigning to myself as I'll pick up the work to move tarmak off run_after_success after 0.6's release.

If anyone doesn't feel like this plan works well, please comment 😄

/assign /milestone v0.7