Use shutil.move instead of os.rename to move config_db.json on place

[leenr]

What I did
I replaced os.rename call with shutil.move.
Also, I reordered imports to be in alphabetical order (cosmetic change).

Why I did it
After sonic-net/sonic-buildimage#20640, SONiC systems mount /tmp as separate tmpfs mount.

SONiC ZTP scripts currently prepares config_dl.json file in /tmp folder and then tries to rename file to /etc/sonic/config_db.json. Earlier there was no issue with that, as /tmp and /etc/sonic was residing on the same mount, on the same device. Now (sonic-buildimage master, and 202505 branch - sonic-net/sonic-buildimage@fbd9252), os.rename raises a OSError: [Errno 18] Invalid cross-device link: '/tmp/config_dl.json' -> '/etc/sonic/config_db.json' exception.

Such behaviour of os.rename is documented:

The operation may fail on some Unix flavors if src and dst are on different filesystems.

I replaced os.rename call with shutil.move (docs) one, which should either use os.rename if such operation is possible, or fall back into "manual" course of actions: first copy the file onto new place, then remove the source file.

I suspect this change will also solve #54, but I'm not entirely sure that the cause was the similar one there.

[linux-foundation-easycla]

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• ✅ login: leenr / name: Vladimir Solomatin (fd57a8c)

[mssonicbld]

/azp run

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[leenr]

/azp run

[azure-pipelines]

Commenter does not have sufficient privileges for PR 66 in repo sonic-net/sonic-ztp

[leenr]

/azpw run

[mssonicbld]

/AzurePipelines run

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Azure Pipelines successfully started running 1 pipeline(s).

[bebeisdog]

I also encountered the same issue. I think this solution is good, but I'm not sure why it hasn't been merged yet. You also explained the root cause

[anders-nexthop]

@yejianquan @rajendra-dendukuri @qiluo-msft for viz