Update LocaleTest.php
minor #8423 Update LocaleTest.php (mikemeier)

This PR was squashed before being merged into the 2.5-dev branch (closes #8423).

Discussion
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Update LocaleTest.php

de_CH locales does not fallback to de
see https://github.com/symfony/symfony/issues/5314

Commits
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572126b Update LocaleTest.php