minor changes in paper and bib for JOSS publication

[danielskatz]

Summary

Please describe what this PR changes as concisely as possible. Link to the issue(s) that this addresses, if any.

Details and comments

Some details that should be in this section include:

• Why this change was necessary
• What alternative solutions were considered and why the current solution was chosen
• What tests and documentation have been added/updated
• What do users and developers need to know about this change

Note that this entire PR description field will be used as the commit message upon merge, so please keep it updated along with the PR. Secondary discussions, such as intermediate testing and bug statuses that do not affect the final PR, should be in the PR comments.

PR checklist (delete when all criteria are met)

• I have read the contributing guide CONTRIBUTING.md.
• I have added the tests to cover my changes.
• I have updated the documentation accordingly.
• I have added a release note file using reno if this change needs to be documented in the release notes.

[CLAassistant]

All committers have signed the CLA.

[eggerdj]

LGTM