SONiC ZTP: Credentials doesn't work after upgrading device from ZTP flow

[esapgan]

Description

Steps to reproduce the issue:

1. Send a new image file using ztp.json and install it as the next boot image
2. The device will be automatically rebooted once the ZTP flow is complete
3. Once the device boots up with the new image, try to login using the default/root creds and it doesn't work.

Describe the results you received:

• Rebooting via ZTP

• Device boots up on the new image, but creds didn’t work

Describe the results you expected:

Once the ZTP is finished and the device boots up with the new image, creds should work to login into the device.

Output of show version:

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Output of show techsupport:

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Additional information you deem important (e.g. issue happens only occasionally):

[adyeung]

@rajendra-dendukuri pls help take a look

[rajendra-dendukuri]

sonic-net/sonic-ztp#42 fixes this issue.