decode binary string as utf-8 in win branch

[bitcloud]

Description
The websocket response can be a string for text or bytes for an utf-8 string. utf-8 was not handled properly. This pr adds detection of bytes and decoding as utf-8 string before writing to the console.
This is the same fix as #18384 applied to the windows code as well.

Fixes: #18251 (comment)

Testing Guide

• start a container e.g. with az container create with a long living container on a Windows system
• try to execute a shell inside the container with az container exec --exec-command "/bin/bash" ...
• currently it just exits without an error or shell

History Notes
[container] az container exec: decode received bytes as utf-8 string (Windows as well now)

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[ghost]

Thank you for your contribution bitcloud! We will review the pull request and get back to you soon.

[bitcloud]

I couldn't test this patch as I don't have a Windows system at hand. But it should work as it seems to be the same issue we had on the linux/macos code path.

[bitcloud]

There seems to be a better PR already on the way: #18909