minor #22224 Fix HttpCache test (chalasr)
minor #22224 Fix HttpCache test (chalasr)

This PR was merged into the 3.3-dev branch.

Discussion
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Fix HttpCache test

| Q             | A
| ------------- | ---
| Branch?       | master
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | no
| Fixed tickets | https://github.com/symfony/symfony/pull/22043#discussion_r107864054
| License       | MIT
| Doc PR        | n/a

will make appveyor green.

Commits
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3178f50594 Fix failing HttpCache test on windows

symfony/HttpKernel,symfony/http-kernel