[TwigBridge] fix  tests
minor #12142 [TwigBridge] fix `DumpExtension` tests (xabbuh)

This PR was squashed before being merged into the 2.6-dev branch (closes #12142).

Discussion
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[TwigBridge] fix `DumpExtension` tests

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

Make test compatible with the changes from #12125.

Commits
-------

e3332ad [TwigBridge] fix  tests
[VarDumper] Sfdump JS ns and VarCloner replacing Ext+PhpCloner