Remove composer cache
Remove composer cache

Not sure if this is causing our flaky tests, but it's something to try.
It wasn't speeding us up that much as the requests to Github itself
seems to run super fast anyway.

thecoolestguy/ilios,Trott/ilios,Trott/ilios,stopfstedt/ilios,thecoolestguy/ilios,dartajax/ilios,dartajax/ilios,ilios/ilios,ilios/ilios,stopfstedt/ilios