fix: use -R in copy_file(is_dir=True) so macos & linux behavior are the same (#3383)

Author: gregmagolan

third_party/github.com/bazelbuild/bazel-skylib/rules/private/copy_file_private.bzl

@@ -85,7 +85,7 @@ def copy_cmd(ctx, src, dst):
 # buildifier: disable=function-docstring
 defcopy_bash(ctx, src, dst):
 ifdst.is_directory:
-cmd_tmpl="rm -rf \"$2\" && cp -rf\"$1/\"\"$2\""
+cmd_tmpl="rm -rf \"$2\" && cp -fR\"$1/\"\"$2\""
 mnemonic="CopyDirectory"
 progress_message="Copying directory %s"%src.path
 else: