Test-infra: mkpj should not fail with anonymous github client

[BenTheElder]

What happened:

While running:
config/mkpj.sh --job=post-kubernetes-push-image-go-runner

The following:

time="2020-05-07T15:26:28Z" level=warning msg="empty -github-token-path, will use anonymous github client"
Base ref (e.g. master): master
time="2020-05-07T15:29:11Z" level=info msg="GetRef(kubernetes, kubernetes, heads/master)" client=github
time="2020-05-07T15:29:12Z" level=debug msg="GetRef(kubernetes, kubernetes, heads/master) finished" client=github duration=215.385334ms
time="2020-05-07T15:29:12Z" level=fatal msg="failed to get base sha: status code 401 not one of [200], body: {\"message\":\"Bad credentials\",\"documentation_url\":\"https://developer.github.com/v3\"}"

What you expected to happen:

I expect to be able to use mkpj on public repos without granting it any authentication.

How to reproduce it (as minimally and precisely as possible):

Use mkpj without --github-token-path

Please provide links to example occurrences, if any:

Anything else we need to know?:

/area prow

[BenTheElder]

you can mitigate by temporarily writing a token to disk and then passing --github-token-path

for this script you probably want to put it in the repo and then do $(pwd)/token since that's already going to be bind mounted.

you should delete this though, do not leave an access token to your github sitting around on your local disk.

[alvaroaleman]

/assign

[alvaroaleman]

This one is really annoying.

[BenTheElder]

thank you!