Previously, the `deploy-to-firebase.js` script would only perform one
deployment operation on each run.
This commit adds support for performing multiple deployment operations.
NOTE:
In a subsequent commit, this will be leveraged fix an issue with
`rc.angular.io` redirects in the presence of a ServiceWorker by
deploying the same artifacts to multiple Firebase projects/sites.
See #39760 for more details.
PR Close#39853
53bd832c77