ci: properly build dev-app for automatic deploy (#28047)

The deploy script seems rather legacy and also doesn't ensure
that the dist directory is actually present. We can simplify
the logic and potentially delete the script in the future.

(cherry picked from commit ff67a41)

Author: devversion

.github/workflows/deploy-dev-app-main-push.yml

@@ -24,7 +24,10 @@ jobs:
       - name: Setup Bazel RBE
         uses: angular/dev-infra/github-actions/bazel/configure-remote@fb30926790c6225d553b91a4818cab2fdde4fb4e
 
-      - run: yarn -s deploy-dev-app
+      - name: Building dev-app
+        run: |
+          yarn -s bazel build //src/dev-app:web_package --symlink_prefix=dist/
+          cp -R dist/bin/src/dev-app/web_package dist/dev-app-web-pkg
 
       - name: Configure Firebase deploy target
         run: |
@@ -39,6 +42,7 @@ jobs:
           repoToken: ''
           firebaseServiceAccount: '${{secrets.FIREBASE_PREVIEW_SERVICE_TOKEN}}'
           projectId: '${{env.PREVIEW_PROJECT}}'
+          entryPoint: './'
           channelId: '${{env.PREVIEW_CHANNEL}}'
 
       - name: Result