ci: fix github_token following README

[alexeagle]

I mistakenly put the bare OAuth token in the credentials file instead of wrapping as a URL

[ngbot]

I see that you just added the PR action: merge label, but the following checks are still failing:
     missing required label: "cla: yes"
     missing required status "continuous-integration/travis-ci/pr"
     missing required status "code-review/pullapprove"
     status "ci/circleci: build-packages-dist" is pending
     status "ci/circleci: lint" is pending
     status "ci/circleci: test" is pending

If you want your PR to be merged, it has to pass all the CI checks.

If you can't get the PR to a green state due to flakes or broken master, please try rebasing to master and/or restarting the CI job. If that fails and you believe that the issue is not due to your change, please contact the caretaker and ask for help.

[angular-automatic-lock-bot]

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