Revert "tree-wide: Don't explicity disable copy-on-write when copying images"

Let's still try to disable COW after copying. It won't do much, but
it doesn't hurt either.

See https://github.com/systemd/systemd/pull/33825/files#r1727288871.

This reverts commit 42e9288180.

src/nspawn/nspawn.c

@@ -6072,8 +6072,10 @@ static int run(int argc, char *argv[]) {
 
                         {
                                 BLOCK_SIGNALS(SIGINT);
-                                r = copy_file(arg_image, np, O_EXCL, arg_read_only ? 0400 : 0600,
-                                              COPY_REFLINK|COPY_CRTIME|COPY_SIGINT);
+                                r = copy_file_full(arg_image, np, O_EXCL, arg_read_only ? 0400 : 0600,
+                                                   FS_NOCOW_FL, FS_NOCOW_FL,
+                                                   COPY_REFLINK|COPY_CRTIME|COPY_SIGINT,
+                                                   NULL, NULL);
                         }
                         if (r == -EINTR) {
                                 log_error_errno(r, "Interrupted while copying image file to %s, removed again.", np);