Docs: Fix incorrect import of useEntityRecords in code example

[t-hamano]

This code example is for useEntityRecords, but it was importing useEntityRecord, so correct the import statement.

Testing Instructions

No impact on the code.

[github-actions]

Flaky tests detected in 070ccaf.
Some tests passed with failed attempts. The failures may not be related to this commit but are still reported for visibility. See the documentation for more information.

🔍 Workflow run URL: https://github.com/WordPress/gutenberg/actions/runs/5308193950
📝 Reported issues:

• [Flaky Test] correctly applies dynamic allowed blocks restrictions #51220 in specs/editor/plugins/inner-blocks-allowed-blocks.test.js