LCP test for checking fetchpriority fails consistently

[jeawhanlee]

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Describe the bug The LCP test that check if fetchpriority is applied to the lcp img tag constantly fails https://github.com/wp-media/wp-rocket-e2e/blob/trunk/src/features/lcp-beacon-image.feature

To Reproduce Steps to reproduce the behavior:

1. Run npm run test:lcp
2. Then see the first test failing.

Expected behavior The test should not fail consistently except when expected.

Screenshots

Additional context Add any other context about the problem here.

Acceptance Criteria (for WP Media team use only)

• Test should pass when expected.