feat(@angular-devkit/build-angular): support using TypeScript 4.1
feat(@angular-devkit/build-angular): support using TypeScript 4.1

ocombe/angular-cli,angular/angular-cli,catull/angular-cli,ocombe/angular-cli,geofffilippi/angular-cli,Brocco/angular-cli,catull/angular-cli,geofffilippi/angular-cli,angular/angular-cli,clydin/angular-cli,catull/angular-cli,catull/angular-cli,ocombe/angular-cli,Brocco/angular-cli,clydin/angular-cli,ocombe/angular-cli,Brocco/angular-cli,geofffilippi/angular-cli,angular/angular-cli,Brocco/angular-cli,ocombe/angular-cli,geofffilippi/angular-cli,angular/angular-cli,clydin/angular-cli,clydin/angular-cli,Brocco/angular-cli