Delete obsolete / unused python test files

Delete obsolete / unused python test files

The python/tests directory contains a number of so called
"tests" for the python API. These are all hardcoded to
look for Xen and cannot be run in any automated fashion,
and no one is ever manually running them. Given that they
don't meaningully contribute to the test coverage, delete
them.

For some reason these tests were also copied into the
filesystem as part of 'make install'. The change to the
RPM in commit 3347a4203278ec93d7b0ceb88b5ed10e4f14765c
caused a build failure, since it removed the code which
deleted these installed tests.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>