PHP 8.1 compatibility - Return type

These issues are also related to deprecation compatibility - Return type. Use phpstan was found next issues:
Line modules/contrib/feeds/libraries/ParserCSV.inc
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32 Return type mixed of method ParserCSVIterator::rewind() is not covariant with tentative return type void of method Iterator::rewind().
💡 Make it covariant, or use the #[\ReturnTypeWillChange] attribute to temporarily suppress the error.
39 Return type mixed of method ParserCSVIterator::next() is not covariant with tentative return type void of method Iterator::next().
💡 Make it covariant, or use the #[\ReturnTypeWillChange] attribute to temporarily suppress the error.
47 Return type mixed of method ParserCSVIterator::valid() is not covariant with tentative return type bool of method Iterator::valid().
💡 Make it covariant, or use the #[\ReturnTypeWillChange] attribute to temporarily suppress the error.
51 Return type mixed of method ParserCSVIterator::current() is not covariant with tentative return type mixed of method Iterator::current().
💡 Make it covariant, or use the #[\ReturnTypeWillChange] attribute to temporarily suppress the error.
59 Return type mixed of method ParserCSVIterator::key() is not covariant with tentative return type mixed of method Iterator::key().
💡 Make it covariant, or use the #[\ReturnTypeWillChange] attribute to temporarily suppress the error.
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Line modules/contrib/feeds/plugins/FeedsParser.inc
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757 Return type mixed of method FeedsDateTime::setTimezone() is not covariant with tentative return type DateTime of method DateTime::setTimezone().
💡 Make it covariant, or use the #[\ReturnTypeWillChange] attribute to temporarily suppress the error.

CI can not apply the patch.