build: remove usage of hash and replace with git diff
build: remove usage of hash and replace with git diff

Between the merge of master and the current branch. This might catch a bit
more but it will work more consistently (especially compared to using the
hash).

ocombe/angular-cli,angular/angular-cli,beeman/angular-cli,catull/angular-cli,manekinekko/angular-cli,geofffilippi/angular-cli,geofffilippi/angular-cli,clydin/angular-cli,hansl/angular-cli,catull/angular-cli,Brocco/angular-cli,filipesilva/angular-cli,DevIntent/angular-cli,geofffilippi/angular-cli,DevIntent/angular-cli,Brocco/angular-cli,manekinekko/angular-cli,DevIntent/angular-cli,filipesilva/angular-cli,Brocco/angular-cli,Brocco/angular-cli,DevIntent/angular-cli,catull/angular-cli,catull/angular-cli,Brocco/angular-cli,filipesilva/angular-cli,angular/angular-cli,angular/angular-cli,clydin/angular-cli,clydin/angular-cli,ocombe/angular-cli,hansl/angular-cli,manekinekko/angular-cli,DevIntent/angular-cli,filipesilva/angular-cli,beeman/angular-cli,clydin/angular-cli,ocombe/angular-cli,ocombe/angular-cli,angular/angular-cli,hansl/angular-cli,ocombe/angular-cli,beeman/angular-cli,geofffilippi/angular-cli,beeman/angular-cli,hansl/angular-cli