Revert "[rust bmp] Add UMA for tracking BMP `CompressionType`."

This reverts commit b44e609869029819e871a5464dd2c2b542bde9da,
because at this point we have gathered all the UMA data that
was needed.

OBSOLETE_HISTOGRAMS=Removed after required data has been gathered - see https://crbug.com/452667935#comment12

Fixed: 452667935
Change-Id: I85739a19b3672f253d77bed113c21e6e0a88e5da
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/7253440
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Commit-Queue: Nicolás Peña <npm@chromium.org>
Auto-Submit: Łukasz Anforowicz <lukasza@chromium.org>
Reviewed-by: Nicolás Peña <npm@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1558307}