Sync UpdatePodSandboxResourcse to implementation

Author: tallclair

keps/sig-node/1287-in-place-update-pod-resources/README.md

@@ -364,11 +364,6 @@ message UpdatePodSandboxResourcesRequest {
     LinuxContainerResources overhead = 2;
     // Optional resources represents the sum of container resources for this sandbox
     LinuxContainerResources resources = 3;
-
-    // Unstructured key-value map holding arbitrary additional information for
-    // sandbox resources updating. This can be used for specifying experimental
-    // resources to update or other options to use when updating the sandbox.
-    map<string, string> annotations = 4;
 }
 
 message UpdatePodSandboxResourcesResponse {}