tomcat8 8.5.34-1ubuntu1: support-jre8.diff and ant-optional version requirement can be removed

I think, support-jre8.diff should be removed from tomcat8 in cosmic. This was fixed upstream in 8.5.33, see also changelog for 8.5.33-1. So I think it should be removed from 8.5.34-1ubuntu1.

This also means that the requirement on ant-optional (>= 1.10.3-2~) can be removed from the control file. It works fine with the older ant-optional version from bionic. (I guess I should report this for Debian.)