runtime/tests: Update annotation for initdata

Let's rename the runtime-rs initdata annotation from
`io.katacontainers.config.runtime.cc_init_data` to
`io.katacontainers.config.hypervisor.cc_init_data`.

Rationale:
- initdata itself is a hypervisor-specific feature
- the new name aligns with the annotation handling logic:
c92bb1aa88/src/libs/kata-types/src/annotations/mod.rs (L514-L968)

This commit updates the annotation for go-runtime and tests accordingly.

Signed-off-by: Hyounggyu Choi <Hyounggyu.Choi@ibm.com>

src/runtime/pkg/oci/utils_test.go

@@ -885,6 +885,9 @@ func TestAddRuntimeAnnotations(t *testing.T) {
 
 	runtimeConfig := RuntimeConfig{
 		HypervisorType: vc.QemuHypervisor,
+		HypervisorConfig: vc.HypervisorConfig{
+			EnableAnnotations: []string{"cc_init_data"},
+		},
 	}
 
 	ocispec.Annotations[vcAnnotations.DisableGuestSeccomp] = "true"

src/runtime/virtcontainers/pkg/annotations/annotations.go

@@ -245,7 +245,7 @@ const (
 	EnableRootlessHypervisor = kataAnnotHypervisorPrefix + "rootless"
 
 	// Initdata is the initdata passed in when CreateVM
-	Initdata = kataConfAnnotationsPrefix + "runtime.cc_init_data"
+	Initdata = kataConfAnnotationsPrefix + "hypervisor.cc_init_data"
 )
 
 // Runtime related annotations