fix(ai-help): destructure embedding response properly

[caugner]

Summary

Problem

The "Update AI Help index" step of our deployment has been failing.

Solution

Properly destructure the CreateEmbeddingResponse.

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Screenshots

Before

 $ ts-node scripts/ai-help.ts update-index
Retrieving all indexed documents...
-> Done.
Determining changed and deleted documents...
-> 1656 of 11955 documents were changed (or added).
-> 26 of 11886 indexed documents were deleted (or moved).
Applying updates...
-> [/en-US/docs/Games] Updating document...
!> [/en-US/docs/Games] Failed to update document. Document has been marked with null checksum to indicate that it needs to be re-generated.
TypeError: undefined is not iterable (cannot read property Symbol(Symbol.iterator))
    at createEmbedding (file:///Users/claas/github/mdn/yari/scripts/ai-help.ts:86:9)
    at processTicksAndRejections (node:internal/process/task_queues:95:5)
    at async updateEmbeddings (file:///Users/claas/github/mdn/yari/scripts/ai-help.ts:165:45)
    at async Se.run (/Users/claas/github/mdn/yari/node_modules/@caporal/core/dist/index.js:1:27579)
    at async Te._run (/Users/claas/github/mdn/yari/node_modules/@caporal/core/dist/index.js:1:32257)
-> [/en-US/docs/Learn] Updating document...
!> [/en-US/docs/Learn] Failed to update document. Document has been marked with null checksum to indicate that it needs to be re-generated.
TypeError: undefined is not iterable (cannot read property Symbol(Symbol.iterator))
    at createEmbedding (file:///Users/claas/github/mdn/yari/scripts/ai-help.ts:86:9)
    at processTicksAndRejections (node:internal/process/task_queues:95:5)
    at async updateEmbeddings (file:///Users/claas/github/mdn/yari/scripts/ai-help.ts:165:45)
    at async Se.run (/Users/claas/github/mdn/yari/node_modules/@caporal/core/dist/index.js:1:27579)
    at async Te._run (/Users/claas/github/mdn/yari/node_modules/@caporal/core/dist/index.js:1:32257)

After

$ ts-node scripts/ai-help.ts update-index
Retrieving all indexed documents...
-> Done.
Determining changed and deleted documents...
-> 1656 of 11955 documents were changed (or added).
-> 26 of 11886 indexed documents were deleted (or moved).
Applying updates...
-> [/en-US/docs/Games] Updating document...
-> [/en-US/docs/Games] Indexing 4 document sections...
-> [/en-US/docs/Learn] Updating document...
-> [/en-US/docs/Learn] Indexing 6 document sections...

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How did you test this change?

Ran yarn ai-help update-index locally with our Supabase Dev project, see above.

[LeoMcA]

lgtm 👍