ARROW-9224: [Dev][Archery] clone local source with --shared

[cyb70289]

archery benchmark diff runs "git clone --local" to clone source code
to /tmp. If /tmp and source directory are at different disk volumes, it
fails because "git clone --local" uses hard links which only works on
same volume. This patch replaces "--local" with "--shared".

Error log:
fatal: failed to create link '/tmp/arrow-archery-lwm7k6wm/origin_master/arrow/.git/objects/2d/80a4d2da431dbfe3c736b6349eb4a0bcb6ece5': Invalid cross-device link
subprocess.CalledProcessError: Command '['git', 'clone', '--local', PosixPath('/home/cyb/arrow'), '/tmp/arrow-archery-lwm7k6wm/origin_master/arrow']' returned non-zero exit status 128.

[github-actions]

https://issues.apache.org/jira/browse/ARROW-9224

[pitrou]

Can you try using git clone --shared instead? It should avoid the copy.

[cyb70289]

Can you try using git clone --shared instead? It should avoid the copy.

--shard works okay per my test. What about simply replacing git clone --local with git clone --shared?
From man page, the only danger of --shared is if I delete and prune the test branch when related test is running, looks not real.

       --shared, -s
           When the repository to clone is on the local machine, instead of using hard links, automatically setup .git/objects/info/alternates to share the
           objects with the source repository. The resulting repository starts out without any object of its own.

           NOTE: this is a possibly dangerous operation; do not use it unless you understand what it does. If you clone your repository using this option
           and then delete branches (or use any other Git command that makes any existing commit unreferenced) in the source repository, some objects may
           become unreferenced (or dangling). These objects may be removed by normal Git operations (such as git commit) which automatically call git gc
           --auto. (See git-gc(1).) If these objects are removed and were referenced by the cloned repository, then the cloned repository will become
           corrupt.

[pitrou]

What about simply replacing git clone --local with git clone --shared?

+1 for me.

[wesm]

thanks!