Implement getTerminalWidth for Windows

[NeonGraal]

Please include the following checklist in your PR:

• Any changes that could be relevant to users have been recorded in the ChangeLog.md
• The documentation has been updated, if necessary.

Please also shortly describe how you tested your change. Bonus points for added tests!

Tests

I temporarily added a putStrLn "!!!" just before the getWidth call in getTerminalWidth to be sure that the function was being called.
I then ran the modified stack with stack run stack -- ls stack-color and got the "!!!"
To check the non-console case I ran the above command with the stdout and stderr redirected to files

[NeonGraal]

Resolve 3588

[snoyberg]

The last comment in the referenced issue (#3588) mentions the terminal-size library. Is there a reason you didn't go with that approach? My concern here is that this change introduces lower bounds on a few packages that ship with GHC, which we typically try to avoid doing.

[NeonGraal]

Ah. I went the way of upgrading an existing dependency rather than including a new one. Didn't realise the lower bounds issue.

At first look using the terminal-size package may actually allow me to delete some code.

Which would you prefer, I commit a revert here and then another with the new change or cancel this PR and raise a new one.

[snoyberg]

No strong preference to be honest, take your pick. If you pushed me for an answer, I'd probably lean towards new PR.

[NeonGraal]

Implemented better in [https://github.com//pull/4797]