Remove unused use statement

[AnshuMishra17]

Description

Removed the unused use statement.

Manual testing scenarios

1. Perform catalog search and advance search from frontend.
2. Save, edit, delete search term and search synonyms in admin.

[magento-engcom-team]

Hi @AnshuMishra17. Thank you for your contribution
Here is some useful tips how you can test your changes using Magento test environment.
Add the comment under your pull request to deploy test or vanilla Magento instance:

• @magento-engcom-team give me test instance - deploy test instance based on PR changes
• @magento-engcom-team give me {$VERSION} instance - deploy vanilla Magento instance

For more details, please, review the Magento Contributor Assistant documentation

[sidolov]

Hi @AnshuMishra17 , due to changes in Magento Code Contributions Guide we can't accept such Pull Requests to 2.2 release line. All code cleanup like typos, spelling mistakes, removing unused code, etc should be delivered to 2.3 release line.
Thank you!