Make passing Travis required for merge.

[saad-ali]

Make passing Travis required for merge

xref kubernetes/test-infra#9014 (comment)

[spiffxp]

When you're ready to implement this, open a PR to https://github.com/kubernetes/test-infra/blob/master/prow/config.yaml

eg: for kubernetes-csi/external-attacher https://github.com/kubernetes/test-infra/blob/master/prow/config.yaml#L172-L175

[lpabon]

🛂 ⛔️
Hi, this repo has been split up into two repos:

• cluster-driver-registrar: Registers the driver with Kubernetes by setting up a CRD
• node-driver-registrar: Registers the driver with the kubelet on the node.

This repo has been closed, and no new changes will be accepted. Please move your content to one of these repos.

Thank you,