Windows and WSL: SI/SO/IBMPC_ON/IBMPC_OFF skip

[penguinolog]

In the case of Windows terminal, output is always Unicode and escape sequences for charset manipulation are "garbage"

Checklist

• I've ensured that similar functionality has not already been implemented
• I've ensured that similar functionality has not earlier been proposed and declined
• I've branched off the master or python-dual-support branch
• I've merged fresh upstream into my branch recently
• I've ran tox successfully in local environment
• I've included docstrings and/or documentation and/or examples for my code (if this is a new feature)

Partial #774

[coveralls]

Pull Request Test Coverage Report for Build 7746319870

• -12 of 14 (14.29%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.02%) to 70.941%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
urwid/display/_raw_display_base.py	2	14	14.29%

Totals
Change from base Build 7739473140:	-0.02%
Covered Lines:	8771
Relevant Lines:	12453

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💛 - Coveralls

[penguinolog]

technically it's not needed at all if console is Unicode but need deeper testing.