chore(ci): avoid unnecessarily running grunt prepareDeploy in deploy-docs CI job

Previously, the `grunt prepareDeploy` command was run in both the
`prepare-deployment` and `deploy-docs` CI jobs. The reason was that not
all files affected by `grunt prepareDeploy` were persisted to the
workspace across jobs.

More specifically, the command would affect files in the `deploy/` and
`scripts/docs.angularjs.org-firebase/` directories and also create a
`firebase.json` file at the root directory, but only the `deploy/`
directory was [persisted to the workspace][1].

This commit avoids unnecessarily running the `grunt prepareDeploy`
command in the `deploy-docs` CI job by ensuring that all affected files
will be persisted to the workspace in the `prepare-deployment` CI job,
which always runs before `deploy-docs`.

[1]: https://github.com/angular/angular.js/blob/295213df953766625462/.circleci/config.yml#L265

Closes #17060

.circleci/config.yml

@@ -342,7 +342,7 @@ jobs:
       - persist_to_workspace:
           root: *workspace_location
           paths:
-            - ./ng/deploy
+            - ./ng
 
   # The `deploy-code` job should only run when all of these conditions are true for the build:
   # - It is for the `angular/angular.js` repository (not a fork).
@@ -383,7 +383,6 @@ jobs:
       - custom_attach_workspace
       - init_environment
       - skip_unless_stable_branch
-      - run: yarn grunt prepareDeploy
         # Install dependencies for Firebase functions to prevent parsing errors during deployment
         # See https://github.com/angular/angular.js/pull/16453
       - run: yarn -cwd ~/ng/scripts/docs.angularjs.org-firebase/functions