Fix admin grid filter backslash escaping issue

[wubinworks]

Fixed admin grid filter backslash escaping issue.

Description (*)

The Admin Grid Filter cannot return correct result for keyword that contains backslash. For example Magento\Store.
This pull request fixed it by escaping backslash.

Related Pull Requests

Fixed Issues (if relevant)

1. Fixes [Small Bug] Filter of Admin Panel listing component cannot hit when field value contains \ #39513

Manual testing scenarios (*)

1. Create a new block in CMS block admin grid with title Magento\Store.
2. Input Magento\Store in title filter to search and then check the search result.
3. The result should contain Magento\Store after merging this branch.

Questions or comments

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)

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[wubinworks]

@magento run all tests