Update _pkgdown.yml

[pdwaggoner]

adding statistical_power per @mattansb

see discussion in #605

[codecov]

Codecov Report

Merging #613 (d91765d) into main (49876e0) will not change coverage.
The diff coverage is n/a.

❗ Current head d91765d differs from pull request most recent head 551cfbd. Consider uploading reports for the commit 551cfbd to get more accurate results

@@           Coverage Diff           @@
##             main     #613   +/-   ##
=======================================
  Coverage   90.55%   90.55%           
=======================================
  Files          56       56           
  Lines        3419     3419           
=======================================
  Hits         3096     3096           
  Misses        323      323           

[pdwaggoner]

Also @DominiqueMakowski - If you could merge this one too, which updates the yml per Mat's suggestion. This is needed in addition to the vignette in #605. Thanks!

[mattansb]

Closing in favor of 397c4cc