python: backport 'Use @asynciocontextmanager'

This removes a non-idiomatic use of a "coroutine callback" in favor of
something a bit more standardized.

Signed-off-by: John Snow <jsnow@redhat.com>
cherry picked from commit python-qemu-qmp@commit 97f7ffa3be17a50544b52767d14b6fd478c07b9e
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
1 file changed