doc: fix url to profile.ts source

[ydewit]

This PR fixes a broken link to the firefox profile definitions in one of the comments.

The profile.js file was renamed to profile.ts while the rest of the url remained the same.

[Copilot]

Pull Request Overview

This PR updates a comment to reflect that the Firefox profiler source file has been renamed from profile.js to profile.ts, correcting the reference link in the code documentation.

• Updated source file reference from profile.js to profile.ts

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[leanprover-community-bot]

Mathlib CI status (docs):

• ❗ Batteries/Mathlib CI will not be attempted unless your PR branches off the nightly-with-mathlib branch. Try git rebase dfd3d185300df044fa087d3fa166cb6fb3bd8269 --onto 7d55c033e1f0ad8cb7c2b9ab72e5db40ce192222. You can force Mathlib CI using the force-mathlib-ci label. (2025-09-30 19:56:49)

[leanprover-bot]

Reference manual CI status:

• ❗ Reference manual CI will not be attempted unless your PR branches off the nightly-with-manual branch. Try git rebase dfd3d185300df044fa087d3fa166cb6fb3bd8269 --onto d3dda9f6d4428a906c096067ecb75e432afc4615. You can force reference manual CI using the force-manual-ci label. (2025-09-30 19:56:51)

[nomeata]

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