Psalm analysis error during Travis CI build

[peter279k]

Travis CI build is failed because the Psalm analysis is failed on following message:

ERROR: NoInterfaceProperties - src/PHPParser/Visitor/DeclarationCollector.php:33:17 - Interfaces cannot have properties (see https://psalm.dev/028)
        $name = $node->namespacedName ?? null;


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1 errors found
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And I think this error should be resolved.