Repair wp/6.4 branch Actions: Fix flaky Pages e2e test Save click - #84621

Part of #82929.

What?

In the Pages › create a new page e2e test (test/e2e/specs/site-editor/pages.spec.js), the Save button click after leaving template editing is now scoped to the editor top bar:

await page
	.getByRole( 'region', { name: 'Editor top bar' } )
	.getByRole( 'button', { name: 'Save', exact: true } )
	.click();

Why?

The test is flaky on this branch. getByRole( 'button', { name: 'Save', exact: true } ) can match two buttons: the editor header's Save button and the Save button in the Site Editor's Navigation sidebar save hub (edit-site-save-hub__button), which appears when there are unsaved changes. Playwright refuses to click when a locator matches more than one element, so the test fails on every attempt in the run when the save hub has rendered:

strict mode violation: getByRole('button', { name: 'Save', exact: true }) resolved to 2 elements:
    1) <button … class="components-button edit-site-save-button__button is-primary">Save</button>
    2) <button … class="components-button edit-site-save-hub__button is-next-40px-default-size is-primary">Save</button>

It failed on #84589 (https://github.com/WordPress/gutenberg/actions/runs/38337028671) and passed when rerun with no change.

How?

Scopes the locator the same way this branch's saveSiteEditorEntities() helper (packages/e2e-test-utils-playwright/src/editor/site-editor.ts) already clicks this button. It was the only unscoped Save click in this branch's site editor specs.

Trunk never fixed this step: it skipped the whole test as flaky in #62799 (June 2024), and the test is still skipped there.

Use of AI Tools

This PR was created by Claude Code under my supervision. All code should be treated as AI-produced and not yet reviewed by a human until this PR is marked Ready for Review.

🤖 Generated with Claude Code