cri: Use the runtimeHandler parameter in PullImage

cri: Use the runtimeHandler parameter in PullImage

The runtimeHandler parameter was added to PullImage() but never used.
Instead, the code relied on an experimental annotation
(io.containerd.cri.runtime-handler) passed in the pod sandbox config.

This annotation was a workaround because CRI's PullImageRequest didn't
include the runtime handler. However, since cri-api v0.29.0, the runtime
handler is available in the API and passed as a parameter to PullImage().

For backward compatibility with CRI clients that don't yet pass the
runtime handler parameter, we fall back to the annotation if the
parameter is empty. The annotation-based fallback is deprecated and
will be removed in containerd 2.5.

Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com>
Signed-off-by: Fabiano Fidêncio <ffidencio@nvidia.com>