Remove a useless check in PrintViewManagerBase::ReleasePrinterQuery()

Replace it with a comment to explain what's going on.

Change-Id: Iafc4489648f5f79984d412fba11e92159143a471
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4351067


Reviewed-by: Andy Phan <andyphan@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1118937}