Fixed the registration of validation.xml file when the form is disabled
bug #9443 [FrameworkBundle] Fixed the registration of validation.xml file when the form is disabled (hason)

This PR was submitted for the 2.1 branch but it was merged into the 2.2 branch instead (closes #9443).

Discussion
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[FrameworkBundle] Fixed the registration of validation.xml file when the form is disabled

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

Commits
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cfa5aa5 [FrameworkBundle] Fixed the registration of validation.xml file when the form is disabled