[Console] Change Command namespaces
minor #3697 [Console] Change Command namespaces (dunglas)

This PR was merged into the master branch.

Discussion
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[Console] Change Command namespaces

| Q             | A
| ------------- | ---
| Doc fix?      | yes
| New docs?     | no
| Applies to    | 2.5

See https://github.com/symfony/symfony-docs/pull/3696#discussion_r10755201

Commits
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0816a07 [Console] Change Command namespaces