ember is marked for autoremoval from testing

[Debian testing autoremoval watch]

ember 0.7.2+dfsg-3 is marked for autoremoval from testing on 2019-12-28

It (build-)depends on packages with these RC bugs:
936279: cegui-mk2: Python2 removal in sid/bullseye
936939: libwfut: Python2 removal in sid/bullseye
937196: opencolorio: Python2 removal in sid/bullseye
943611: cegui-mk2: cegui-mk2 fails to package extensions for python 3.8
944742: assimp: testsuite regression