Prevent nil pointer deref in GetImage

Trying to print the image id on a failed inspect will result in a nil
pointer panic because the image will be nil.  Replace image.id with the
image name which is defined as a string without the use of inspect.

Fixes: bz#2131836

[NO NEW TESTS NEEDED]

Signed-off-by: Brent Baude <bbaude@redhat.com>

pkg/api/handlers/compat/images.go

@@ -403,7 +403,7 @@ func GetImage(w http.ResponseWriter, r *http.Request) {
 	}
 	inspect, err := handlers.ImageDataToImageInspect(r.Context(), newImage)
 	if err != nil {
-		utils.Error(w, http.StatusInternalServerError, fmt.Errorf("failed to convert ImageData to ImageInspect '%s': %w", inspect.ID, err))
+		utils.Error(w, http.StatusInternalServerError, fmt.Errorf("failed to convert ImageData to ImageInspect '%s': %w", name, err))
 		return
 	}
 	utils.WriteResponse(w, http.StatusOK, inspect)