tests: nydus: Add uid / namespace to the nydus container / sandbox

Otherwise we may face errors like:
```
getting sandbox status of pod "d3af2db414ce8": metadata.Name,
metadata.Namespace or metadata.Uid is not in metadata
"&PodSandboxMetadata{Name:nydus-sandbox,Uid:,Namespace:default,Attempt:1,}"

getting sandbox status of pod "-A": rpc error: code = NotFound desc = an
error occurred when try to find sandbox: not found
```

Signed-off-by: Fabiano Fidêncio <fabiano.fidencio@intel.com>

tests/integration/nydus/nydus-container.yaml

@@ -1,5 +1,7 @@
 metadata:
   name: nydus-container
+  namespace: default
+  uid: nydus-containerd-uid
 image:
   image: ghcr.io/dragonflyoss/image-service/alpine:nydus-latest
 command:

tests/integration/nydus/nydus-sandbox.yaml

@@ -2,4 +2,5 @@ metadata:
   attempt: 1
   name: nydus-sandbox
   namespace: default
+  uid: nydus-sandbox-uid
 log_directory: /tmp