STT: Remove some dist artifacts from test build

They consume much disk space even though they are not used.

Bug: 284915566
Test: combined_build_test.sh -t cf_x86_64_phone -v userdebug \
                     -d out/dist -a cf_x86_64_foldable -o -c droid
Change-Id: I4fd5e9326e5c77c28c5e178f63ba396c9e462cbd
1 file changed