[nextest-runner] add verbose flag to display test command lines

[dangvu0502]

Fixes #2513

[codecov[bot]]

Codecov Report

:x: Patch coverage is 91.48936% with 4 lines in your changes missing coverage. Please review. :white_check_mark: Project coverage is 80.19%. Comparing base (689de58) to head (4c56227). :warning: Report is 11 commits behind head on main.

Files with missing lines	Patch %	Lines
nextest-runner/src/reporter/displayer/imp.rs	55.55%	4 Missing :warning:

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2800      +/-   ##
==========================================
+ Coverage   80.17%   80.19%   +0.02%     
==========================================
  Files         113      113              
  Lines       26312    26359      +47     
==========================================
+ Hits        21095    21139      +44     
- Misses       5217     5220       +3     

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[dangvu0502]

Implementation updated based on feedback

[sunshowers]

With apologies, I need to tackle something urgently at work this week. Hoping to look at this by the end of the week.