libct/cg/sd: Add freezer tests
libct/cg/sd: Add freezer tests

This test the issues fixed by the two preceding commits.

Co-Authored-By: Kir Kolyshkin <3a017b8ddb3f9cf3e4a59978b004111bdeb97f08@gmail.com>
Signed-off-by: Odin Ugedal <a12bf2c17c422acccb707fa811f07e743a9293d8@uged.al>
Signed-off-by: Kir Kolyshkin <3a017b8ddb3f9cf3e4a59978b004111bdeb97f08@gmail.com>

kolyshkin/runc,dqminh/runc,opencontainers/runc,kolyshkin/runc,dqminh/runc,rhatdan/runc,opencontainers/runc,kolyshkin/runc,opencontainers/runc,dqminh/runc,rhatdan/runc,kolyshkin/runc,dqminh/runc,opencontainers/runc,rhatdan/runc,rhatdan/runc