Remove some <selectlist> image resources

These were used for the <selectlist> element which has already been
removed.

Change-Id: I73db72dea972e2d3b70e6071f8592249355d4c50
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6103162
Reviewed-by: Di Zhang <dizhangg@chromium.org>
Commit-Queue: Joey Arhar <jarhar@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1398785}