justinsb: Fix cluster list action

JobBuild
12075
07-30 13:55
pull-kops-bazel-build 1421106945376391168
pull-kops-bazel-test 1421106945409945600
pull-kops-e2e-kubernetes-aws 1421106945351225344
pull-kops-verify-bazel 1421106945477054464
pull-kops-verify-boilerplate 1421106945598689280
pull-kops-verify-generated 1421106945502220288
pull-kops-verify-gofmt 1421106945636438016
pull-kops-verify-gomod 1421106945548357632
pull-kops-verify-govet 1421106945665798144
pull-kops-verify-staticcheck 1421106945707741184