feat: support hyphen values for --build-jobs

[mattsse]

cargo --jobs supports negative values: rust-lang/cargo#9217

currently this fails:

cargo nextest run --build-jobs -1                                                                                                                                                                                                   
error: unexpected argument '-1' found

  tip: to pass '-1' as a value, use '-- -1'

because clap doesn't support this by default and requires allow_hyphen_values = true

clap-rs/clap#1245

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 79.65%. Comparing base (f6064a0) to head (8d6c414).
Report is 2 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1874   +/-   ##
=======================================
  Coverage   79.64%   79.65%           
=======================================
  Files          80       80           
  Lines       20406    20409    +3     
=======================================
+ Hits        16253    16256    +3     
  Misses       4153     4153           

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[sunshowers]

Thank you! Could you also add a test here?

nextest/cargo-nextest/src/dispatch.rs

Line 2350 in 8668970

let valid: &[&'static str] = &[

[sunshowers]

Thank you!