Fixes #6392 Optimize WP Query in `rocket_url_to_postid()`

[remyperona]

Description

Optimize the query by passing the args to prevent caching and found rows calculation.

Fixes #6392

Type of change

• Enhancement (non-breaking change which improves an existing functionality).

Is the solution different from the one proposed during the grooming?

No grooming, small change.

Checklists

Generic development checklist

• [x] My code follows the style guidelines of this project, with adapted comments and without new warnings.
• [x] The CI passes locally with my changes (including unit tests, integration tests, linter).

Test summary

• [x] I triggered all changed lines of code at least once without new errors/warnings/notices.
• [ ] I validated all Acceptance Criteria of the related issues. (If applicable, provide proof).
• [ ] I validated all test plan the QA Review asked me to.

[Mai-Saad]

Related initial test plan https://wpmediaqa.testrail.io/index.php?/runs/view/816&group_by=cases:section_id&group_order=asc

[hanna-meda]

Moved this to QA done for now without merging it until we check the 2 blocked tests in here.