Gulp Build: fix to populate modules list when gulp bundle is executed (#6331)
Gulp Build: fix to populate modules list when gulp bundle is executed (#6331)

* added support for pubcommon, digitrust, id5id

* added support for IdentityLink

* changed the source for id5

* added unit test cases

* changed source param for identityLink

* need to update modules list when gulp bundle is called

* added a comment
prebid/Prebid.js,PubWise/Prebid.js,mcallari/Prebid.js,prebid/Prebid.js,PWyrembak/Prebid.js,gumgum/Prebid.js,gumgum/Prebid.js,ImproveDigital/Prebid.js,Niksok/Prebid.js,tchibirev/Prebid.js,prebid/Prebid.js,HuddledMasses/Prebid.js,HuddledMasses/Prebid.js,PubWise/Prebid.js,gumgum/Prebid.js,Niksok/Prebid.js,PubWise/Prebid.js,mcallari/Prebid.js,ImproveDigital/Prebid.js,ImproveDigital/Prebid.js,HuddledMasses/Prebid.js,Niksok/Prebid.js,tchibirev/Prebid.js,PWyrembak/Prebid.js,PWyrembak/Prebid.js