CUNY Academic Commons

In https://github.com/cuny-academic-commons/cac/commit/4100d60877da7f50b6479673b32dd6da27438aba I bumped the PHPCompatibility sniffs to 7.4 (and fixed a bug that made it impossible to test the entire codebase properly).

In https://github.com/cuny-academic-commons/cac/commit/3c06e2593a2cd037c4740868ee2fd013d596139e I made a change so that CircleCI runs PHP 7.4, ensuring that the php -l lint tool will work properly.

Whoops, we already have a ticket for this :) #12551