build: Remove unused generateDocs.sh script
build: Remove unused generateDocs.sh script

Plain 'jsduck' works now. Jenkins hasn't used this script for a
while now. Builds for specific releases are provided by url on
doc.wikimedia.org and JSDuck no claims "master" or a version in
its output.

Change-Id: Ifbb72f27316a6f15b7bcef3f43f5de700a35e460

wikimedia/oojs,iSCInc/oojs,wikimedia/oojs