Fix windows hostonly_devicelab tests.

[godofredoc]

Description

Tests have been failing because windows 10 files use \r\n instead of just \n for file separators. Because of this the test was not replacing the assets/modules in pusbspec files.

Related Issues

Bug:
#64466

Tests

I added the following tests:

N/A

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[keyonghan]

Is this intended to remove?

[godofredoc]

Yes, that one is still failing consistently.

[keyonghan]

LGTM