Disallow self-LGTMs
Disallow self-LGTMs

As https://github.com/opencontainers/project-template/pull/13
is merged, change pullapprove accordingly.

Signed-off-by: Qiang Huang <488e06933c295c76472a67dbc6657ac40a756953@huawei.com>

wking/opencontainer-specs,wking/opencontainer-runtime-spec,cloudfoundry-incubator/specs,jonboulle/specs,vbatts/specs,ujuc/specs,hqhq/runtime-spec,laijs/specs,hqhq/specs,opencontainers/runtime-spec,opencontainers/specs