Remove Python opcode test 'TestClusterOsList'
Remove Python opcode test 'TestClusterOsList'

Python opcode generation produces also calls to Python type predicates
in a more composable way compared to the previous hand-written type
predicates. As a result, some predicates, such as,
'TestClusterOsList', became unused because they are achieved through a
combination of other predicates.

Signed-off-by: Jose A. Lopes <0fb9c4f8511df4ec2ae28af879e9d462f6218a2c@google.com>
Reviewed-by: Guido Trotter <f62ca4d5358bdaeef0e50e57f9f7e231de63727e@google.com>

andir/ganeti,leshchevds/ganeti,apyrgio/snf-ganeti,bitemyapp/ganeti,mbakke/ganeti,ganeti/ganeti,apyrgio/snf-ganeti,mbakke/ganeti,yiannist/ganeti,onponomarev/ganeti,dimara/ganeti,yiannist/ganeti,bitemyapp/ganeti,onponomarev/ganeti,grnet/snf-ganeti,ganeti/ganeti,andir/ganeti,yiannist/ganeti,ganeti/ganeti,apyrgio/ganeti,ganeti-github-testing/ganeti-test-1,ganeti-github-testing/ganeti-test-1,leshchevds/ganeti,dimara/ganeti,grnet/snf-ganeti,mbakke/ganeti,andir/ganeti,leshchevds/ganeti,apyrgio/ganeti