bug #54191 [Validator] add missing invalid extension error entry (xabbuh)

This PR was merged into the 6.4 branch.

Discussion
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[Validator] add missing invalid extension error entry

| Q             | A
| ------------- | ---
| Branch?       | 6.4
| Bug fix?      | yes
| New feature?  | no
| Deprecations? | no
| Issues        | Fix #54170
| License       | MIT

Commits
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999f713673 add missing invalid extension error entry

Author: nicolas-grekas

Constraints/File.php

@@ -41,6 +41,7 @@ class File extends Constraint
         self::EMPTY_ERROR => 'EMPTY_ERROR',
         self::TOO_LARGE_ERROR => 'TOO_LARGE_ERROR',
         self::INVALID_MIME_TYPE_ERROR => 'INVALID_MIME_TYPE_ERROR',
+        self::INVALID_EXTENSION_ERROR => 'INVALID_EXTENSION_ERROR',
         self::FILENAME_TOO_LONG => 'FILENAME_TOO_LONG',
     ];