Updates needed for Autoprefixer #162
Description
Autoprefixer has just (v9.7.1) fixed a bug where width: fit-content wasn't getting a -moz prefix for Firefox (postcss/autoprefixer#1207). Can we update the dependency to get this fix?
Also of note: browsers is no longer supported as an option for browserslist, it now expects overrideBrowserslist. The claycli default is still using browsers (https://github.com/clay/claycli/blob/master/lib/compilation-helpers.js#L191)