As we can see in the CI Job log here: https://travis-ci.org/github/coreos/go-oidc/jobs/702172636 from this PR: #254 , the job failed because we write unit test calling t.Cleanup() func, and this func is only supported in go v1.14, meanwhile we use go v1.12 and v1.13 in the .travis.yml.

So I propose to change the go version used in .travis.yml to v1.14 only. Is there any concern?

Thank you