[Port-2.3] Fix docBlock for hasInvoices(), hasShipments(), hasCreditmemos()

[gelanivishal]

Original Pull Request

#16554

Description

Small improvements of docBlock for app/code/Magento/Sales/Model/Order.php docBlock description.
hasInvoices(), hasShipments(), hasCreditmemos() returns int and not bool

Manual testing scenarios

No testing scenarios, just docBlock changed

Contribution checklist

• Pull request has a meaningful description of its purpose
• All commits are accompanied by meaningful commit messages
• All new or changed code is covered with unit/integration tests (if applicable)
• All automated tests passed successfully (all builds on Travis CI are green)

[magento-engcom-team]

Hi @gelanivishal. Thank you for your contribution
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Add the comment under your pull request to deploy test or vanilla Magento instance:

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[sidolov]

Hi @gelanivishal , unfortunately, ew can't accept this pull request, direct typecasting more faster than using casting functions, I'm closing this PR as not relevant.