cft: remove depricated docker files

All of these have been moved into test/dockerfiles/* and are
building/working (Except callbox, but thats not being built anyways
currently).

BUG=b:230875828
TEST=see results from here https://ci.chromium.org/ui/p/chromeos/builders/postsubmit/grunt-postsubmit/15145/overview

Change-Id: Ifbf1d2f51c6fae0b013dfa5945761284a7ab74d6
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/dev-util/+/3647003
Reviewed-by: Jaques Clapauch <jaquesc@google.com>
Commit-Queue: Derek Beckett <dbeckett@chromium.org>
Tested-by: Derek Beckett <dbeckett@chromium.org>
14 files changed