Fix terminal width detection on macOS

[electrum]

stty on macOS outputs the value before the name, like this:

speed 9600 baud; 40 rows; 80 columns;

Rather than trying to fix the regex to match either one, we can use the simpler tputs cols command.

[codecov-commenter]

Codecov Report

Merging #1150 into master will increase coverage by 0.01%.
The diff coverage is 50.00%.

@@             Coverage Diff              @@
##             master    #1150      +/-   ##
============================================
+ Coverage     94.28%   94.30%   +0.01%     
  Complexity      455      455              
============================================
  Files             2        2              
  Lines          6665     6667       +2     
  Branches       1790     1792       +2     
============================================
+ Hits           6284     6287       +3     
+ Misses          104      102       -2     
- Partials        277      278       +1     

Impacted Files	Coverage Δ	Complexity Δ
src/main/java/picocli/CommandLine.java	94.14% <50.00%> (+0.01%)	314.00 <0.00> (ø)

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[remkop]

Merged into master.
I guess this never worked on macOS; unfortunately I don't have access to a mac so I could not test...
Thank you very much for your contribution!

[remkop]

@electrum Picocli 4.5.1 has been released, including your fix for this issue.
Thanks again for the contribution!

[electrum]

Thanks @remkop! I tested that version and confirmed the wrapping works.

[remkop]

Excellent!
Thanks again for the contribution!