This issue is automatically created based on existing pull request: #37462: Sitemap fix error in case of image with null Title or Caption

Description (*)

This patch fixes Patch to fix Argument 1 passed to Magento\Sitemap\Model\Sitemap::escapeXmlText() must be of the type string, null given when the given title or caption are null.

Manual testing scenarios (*)

1. Add a sitemap image with a title or caption with the value null.
2. The Sitemap model should no longer return an error.

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)
• README.md files for modified modules are updated and included in the pull request if any README.md predefined sections require an update
• All automated tests passed successfully (all builds are green)