Fix process.CI typo

[istarkov]

Closes #12145

[gaearon]

Do we have a check like this anywhere else?

[istarkov]

No, from what I see, just similar check on process.env.CI_PULL_REQUEST
which is not same as CI

CI_PULL_REQUEST

If this build is part of only one pull request, its URL will be populated here. If there was more than one pull request, it will contain one of the pull request URLs (picked randomly)

There are also check here

const isCI = !!process.env.TRAVIS_REPO_SLUG;

seems like will not work at CI at all

[istarkov]

Seems like tests fail is circle cache or similar issue.