ci(docs-infra): remove unnecessary command (#26202)

This was accidentally merged with 4d506acba and 87f60bccf.
The build script is called in `scripts/ci/build.sh` (if necessary).

PR Close #26202

scripts/ci/install.sh

@@ -55,9 +55,6 @@ if [[ ${TRAVIS} &&
   # angular.io: Install all yarn dependencies according to angular.io/yarn.lock
   travisFoldStart "yarn-install.aio"
     (
-      # HACK (don't submit with this): Build Angular
-      ./build.sh --packages=compiler,core,elements --examples=false
-
       cd ${PROJECT_ROOT}/aio
       yarn install --frozen-lockfile --non-interactive
     )