The DirCopy() function in "graphdriver/copy/copy.go" has a special case for
skip file-attribute copying when making a hard link to an already-copied
file, if "copyMode == Hardlink". Do the same for copies of hard-links in
the source filesystem.
Significantly speeds up vfs's copy of a BusyBox filesystem (which
consists mainly of hard links to a single binary), making moby's
integration tests run more quickly and more reliably in a dev container.
Fixes#46810
Signed-off-by: Rob Murray <rob.murray@docker.com>
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