Remove pnpm debug log

- it is contained within `node_modules/`, which is already ignored
- the previous versions, which were not in `node_modules/`, did not have a period at the beginning of the filename

Changelog with proof here:

https://github.com/pnpm/pnpm/blob/ba4b2db1f201640dad5d7ee9fe68a2d0defd6047/pnpm/CHANGELOG.md?plain=1#L3330