ref: `import-url/update --jobs` affects uploading with `--to-remote`

[jorgeorpinel]

--jobs (also) affects the uploading when using dvc import-url --to-remote so the description should be updated. This also affects dvc update.

Originally posted by @daavoo in #3199 (review)

[jorgeorpinel]

AFAIK --to-remote "streams" chunks of the data via the local env into the remote. Do you mean that --jobs affects this whole transferring strategy (both download and upload) but has no effect for downloading regular imports (without --to-remote) @daavoo ? Thanks

[jorgeorpinel]

I think the intuitive behavior *shoud* be that the number of --jobs applies to both downloading and uploading with or without --to-remote. If anyone can confirm we'll update the refs cc @dberenbaum @efiop thanks

[daavoo]

It affects both, I meant to say --jobs also affects the uploading

[jorgeorpinel]

Would you like to contribute this reference fix @daavoo ?