Add skip flags for block level live migration

This has been observed recently that block level live
migration started failing with micro version 2.24 if the
user doesn't mention the "block_migration_for_live_migration"
it adds none in the api and thus tries to run it as shared
storage live migration and thus the test failed.

Change-Id: I4a3c1b83ee51a03a49f96b83e020419a306a15b3
Closes-Bug: 1884832
1 file changed