docs: fix link to node-tracking.js file (#10429)
docs: fix link to node-tracking.js file (#10429)

I was reading the docs and I found that the link to `node-tracking.js` was taking me to Github's 404 page, so I looked into the repo and found it had been moved from `/schema` to `/db`.
I checked the referenced lines (9 and 32) and they do match the function names cited in the docs.

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