Remove Note from HRI'25 paper

[amalnanavati]

Although #111 added the HRI paper, it rendered redundantly on the website:

1. Because it specified the url field, the link on the title went to the paper's website instead of the PDF.
2. Because it specified the note field, a link to the website also appeared below the paper's citation.

Upon discussion with @adlarkin, we agreed that having the paper title link to the website is better than having a separate note below the paper. Thus, this PR removes the note field of this pub.

Policy for linking to a website instead of a paper PDF:

1. Ensure the website is permanently hosted (i.e., it shouldn't be affiliated with an account that could get deactivated).
2. Ensure the website links to the paper within the personalrobotics.cs.washington.edu domain (e.g., https://personalrobotics.cs.washington.edu/publications/nanavati2025lessons.pdf ).
3. Specify the url field in the bibtex to override the title link.

[adlarkin]

Thanks!