Fix assorted warnings in console when running docs

[lavelle]

None of these seems to be errors, but they are clutter and should be removed.

warn "export 'UserAvatarProps' was not found in './components/Avatar/index'. This can be fixed with a new version of Webpack/TypeScript, which will probably happen automatically as part of moving to NextJS

Deprecation Warning: Using / for division outside of calc() is deprecated and will be removed in Dart Sass 2.0.0.. For this we need to remove the deprecated docsearch.js package and replace it with @docsearch/js.

DeprecationWarning: Invalid 'main' field in '/thumbprint/node_modules/find-parent-dir/package.json' of 'find-parent-dir.js'.. Haven't dug into this one yet. Presumably need to make some changes to the find-parent-dir script.

cc @danoc