[FrameworkBundle] Fixed bug in XMLDescriptor
bug #9768 [FrameworkBundle] Fixed bug in XMLDescriptor (Exelenz)

This PR was squashed before being merged into the 2.4 branch (closes #9768).

Discussion
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[FrameworkBundle] Fixed bug in XMLDescriptor

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

Fixed bug in container:debug command where parameter value doesn't get printed.

Commits
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34d0b1d [FrameworkBundle] Fixed bug in XMLDescriptor