fix typo in test skipped message
merged branch Inori/2.1 (PR #8855)

This PR was submitted for the 2.1 branch but it was merged into the 2.2 branch instead (closes #8855).

Discussion
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[HttpFoundation] [Tests] fix typo in Memcached tests skipped message

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

Commits
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83e4fcf fix typo in test skipped message