minor #14122 [VarDumper] Fix tests typo (ogizanagi)
minor #14122 [VarDumper] Fix tests typo (ogizanagi)

This PR was merged into the 2.7 branch.

Discussion
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[VarDumper] Fix tests typo

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | ✘
| License       | MIT
| Doc PR        | ✘

I guess there is a typo here, Travis reported (php >=5.6, see https://travis-ci.org/symfony/symfony/jobs/56527757 for instance):
> 1) Symfony\Component\VarDumper\Tests\CliDumperTest::testSpecialVars56
Undefined variable: out
/home/travis/build/symfony/symfony/vendor/symfony/phpunit-bridge/Symfony/Bridge/PhpUnit/DeprecationErrorHandler.php:38
/home/travis/build/symfony/symfony/src/Symfony/Component/VarDumper/Tests/CliDumperTest.php:218

Commits
-------

c5f39aa [VarDumper] CliDumper: fix test typo

symfony/var-dumper,symfony/var-dumper