[WebProfilerBundle] Fixed invalid condition in form panel
bug #9316 [WebProfilerBundle] Fixed invalid condition in form panel (bschussek)

This PR was merged into the master branch.

Discussion
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[WebProfilerBundle] Fixed invalid condition in form panel

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

Before, the children of a form with just one child were not shown. This is fixed now.

Commits
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f21de87 [WebProfilerBundle] Fixed invalid condition in form panel