[OOBE] Dedupe query selectors in update.ts and consumer_update.ts

Bug: b/314762334
Change-Id: I58038d7217cb869326eb631ca601e007cf11eca9
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5214372
Auto-Submit: Simon Ziegltrum <ziegltrum@google.com>
Commit-Queue: Simon Ziegltrum <ziegltrum@google.com>
Commit-Queue: Danila Kuzmin <dkuzmin@google.com>
Reviewed-by: Danila Kuzmin <dkuzmin@google.com>
Cr-Commit-Position: refs/heads/main@{#1249372}