Settings Split: Fix typo in pref_registry

Bug: b/241965700
Change-Id: I0008e2400b8846903c84a5408cce49cb14ba9ee5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4382728


Commit-Queue: David Padlipsky <dpad@google.com>
Reviewed-by: David Padlipsky <dpad@google.com>
Commit-Queue: Michael Checo <michaelcheco@google.com>
Auto-Submit: Michael Checo <michaelcheco@google.com>
Cr-Commit-Position: refs/heads/main@{#1123739}