Writing prompts: get prompt by id when answering a specific prompt

[creativecoder]

Fixes Automattic/wp-calypso#71938

Proposed changes:

When answering a writing prompt, fetch by the specified prompt id, rather than using the current date.

The main benefit is that older links for past daily prompts in email or notifications will continue to work with the correct prompt.

Other information:

• Have you written new tests for your changes, if applicable?
• Have you checked the E2E test CI results, and verified that your changes do not break them?
• Have you tested your changes on WordPress.com, if applicable (if so, you'll see a generated comment below with a script to run)?

Jetpack product discussion

pe7F0s-uo-p2

Does this pull request change what data or activity we track or use?

No.

Testing instructions:

Note: requires the wpcom patch D100649-code

• Activate the experimental editor extensions with define( 'JETPACK_EXPERIMENTAL_BLOCKS', true );, or the option in the Jetpack beta plugin
• Apply the diff D100649-code to your wpcom sandbox and specify your sandbox domain using the JETPACK__SANDBOX_DOMAIN constant.
• Specify a prompt id when creating a new post, such as /wp-admin/post-new.php?answer_prompt=1810
• You should see that prompt displayed as a pullquote in the editor.
• Start a new post with a non-existant prompt id, like /wp-admin/post-new.php?answer_prompt=1, and you should see a fallback prompt.

[github-actions]

Are you an Automattician? You can now test your Pull Request on WordPress.com. On your sandbox, run

bin/jetpack-downloader test jetpack update/get-blogging-prompts-by-id

to get started. More details: p9dueE-5Nn-p2

[github-actions]

Thank you for your PR!

When contributing to Jetpack, we have a few suggestions that can help us test and review your patch:

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Jetpack plugin:

• Next scheduled release: March 7, 2023.
• Scheduled code freeze: February 28, 2023.

[jeherve]

This tests well for me. 🚢

[creativecoder]

Closing, as this will be replaced by #29433