Add tests to CMake project

Related to https://github.com/xiph/vorbis/issues/73.

Signed-off-by: Ralph Giles <giles@thaumas.net>
2 jobs for master in 1 minute and 46 seconds (queued for 1 second)
latest
Status Job ID Name Coverage
  Build
passed #10949
docker
autoconf

00:01:46

passed #10950
docker
cmake

00:00:35