Update doc and tests after latest loo pkg release

[jgabry]

Submission Checklist

• Run unit tests
• Declare copyright holder and agree to license (see below)

Summary

Fixes a failing test and updates some doc affected by the latest loo package release.

Copyright and Licensing

Please list the copyright holder for the work you are submitting
(this will be you or your assignee, such as a university or company):
Columbia University

By submitting this pull request, the copyright holder is agreeing to
license the submitted work under the following licenses:

• Code: BSD 3-clause (https://opensource.org/licenses/BSD-3-Clause)
• Documentation: CC-BY 4.0 (https://creativecommons.org/licenses/by/4.0/)

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 88.32%. Comparing base (d3b455f) to head (1e38769).

❗ Current head 1e38769 differs from pull request most recent head c881c9b. Consider uploading reports for the commit c881c9b to get more accurate results

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #923   +/-   ##
=======================================
  Coverage   88.32%   88.32%           
=======================================
  Files          12       12           
  Lines        4548     4548           
=======================================
  Hits         4017     4017           
  Misses        531      531           

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[jgabry]

Just minor edits to doc and one test, so will go ahead and merge