test(aio): fix running docs examples against local builds (#18520)

This commit also updates the version of `@angular/cli` used for docs examples.
The previous (transient) dependency `@ngtools/webpack` was not compatible with
`@angular/compiler-cli@>=5` and was breaking when running against the local
builds (currently at 5.0.0-beta.2). The version of `@ngtools/webpack` used by
the latest `@angular/cli` version is compatible with `@angular/compiler-cli@5`.

scripts/ci/build.sh

@@ -40,6 +40,16 @@ if [[ ${CI_MODE:-} == "aio" ]]; then
   exit 0;
 fi
 
+# Build the Angular packages then exit (no further build required)
+if [[ ${CI_MODE:-} == "aio_e2e" ]]; then
+  travisFoldStart "build.aio_e2e"
+  (
+    ./build.sh
+  )
+  travisFoldEnd "build.aio_e2e"
+  exit 0;
+fi
+
 travisFoldStart "tsc tools"
   $(npm bin)/tsc -p tools
   cp tools/@angular/tsc-wrapped/package.json dist/tools/@angular/tsc-wrapped